Predicting who will play best: The top 25 NBA free agents

— -- Which free agents will be the most productive over the next three seasons? We have the 25 best, based on my projections.

To rank the best players in free agency, I used my SCHOENE projection system to forecast how free agents will perform over the next three seasons. I also factored in ESPN's real plus-minus to come up with a comprehensive estimate of how many wins above replacement player (WARP) players will provide over that span, which is a good trade-off between the short- and long-term considerations that go into free agency.

While these rankings are topped by the names you might expect, there are also a few surprising favorites of all-in-one stats within the top 25.

1. LeBron James

Cleveland Cavaliers
Forward
Age: 31
Unrestricted

Projected 3-Year WARP: 52.1 |   2015-16 RPM: 8.4 | 2015-16 WARP: 17.8

At 31, James has already established himself as one of the greatest players in NBA history, and his playoff performance en route to winning a third championship re-established him as the best player in the league. Though that status won't continue forever, based on similar players, SCHOENE doesn't foresee much of a decline for James over the next three seasons.

2. Kevin Durant

Oklahoma City Thunder
Forward
Age: 27
Unrestricted

Projected 3-Year WARP: 41.0 |   2015-16 RPM: 6.1 | 2015-16 WARP: 17.7

Update (July 4):  Kevin Durant agreed to a two-year, $54 million deal with the Golden State Warriors. 

With James indicating he's headed back to Cleveland to defend the title, Durant is the best free agent realistically on the market. His projection is a bit more conservative since similar players did drop off a bit in their late 20s, but that shouldn't be a concern for possible suitors. Barring injury, Durant will remain one of the league's top stars through his next contract.

3. Andre Drummond

Detroit Pistons
Center
Age: 22
Restricted

Projected 3-Year WARP: 32.6 |   2015-16 RPM: 2.9 | 2015-16 WARP: 12.1

Update (July 1):  Drummond has agreed to a five-year, $130 million max deal with the Detroit Pistons.

At the age of 22, Drummond finished 16th in the league in WARP last season, his first as an All-Star. Drummond's box-score stats may not improve much, but as he grows more experienced and improves his decision-making, he figures to solidify his spot as an All-NBA contender at center.

4. Hassan Whiteside

Miami Heat
Center
Age: 27
Unrestricted

Projected 3-Year WARP: 28.7 |   2015-16 RPM: 1.0 | 2015-16 WARP: 15.5

Update (July 1):  Whiteside has agreed to a four-year max contract with the Miami Heat.

Because of his high-percentage scoring, prodigious rebounding and league-leading block total, Whiteside actually ranked in the top 10 in WARP. His team impact wasn't that strong, so Whiteside was barely better than league average in RPM. The combination of the two metrics puts him a bit behind Drummond as the second-best center available, though still in front of the older max free agents.

5. Al Horford

Atlanta Hawks
Forward/center
Age: 30
Unrestricted

Projected 3-Year WARP: 23.1 |   2015-16 RPM: 3.1 | 2015-16 WARP: 10.6

Update (July 2):  Horford agreed to a four-year, $113 million deal with the Boston Celtics.

Although Horford's 2016-17 projection puts him not far behind Drummond and Whiteside, at age 30, he's more likely to decline going forward. These three-year projections don't capture the entirety of the four-year deal other teams can offer, let alone the five years Horford could get from the Hawks.

Before the season, FiveThirtyEight's CARMELO projection system suggested Horford will likely be barely better than replacement level by 2020-21.

6. Mike Conley

Memphis Grizzlies
Guard
Age: 28
Unrestricted

Projected 3-Year WARP: 20.3 |   2015-16 RPM: 2.6 | 2015-16 WARP: 6.6

Update (July 1):  Mike Conley and the Memphis Grizzlies have agreed in principle on a five-year, $153 million deal.

As a small point guard, Conley might be an even bigger long-term risk than Horford, though his CARMELO projection is a bit more positive. Nonetheless, as Danny Leroux pointed out on Twitter, just three players 6-foot-3 or shorter have started at least 50 games in one of the past five seasons at age 32 or older: Jose Calderon, Steve Nash and Tony Parker. Conley will turn 32 in Year 4 of a new contract.

7. Nicolas Batum

Charlotte Hornets
Forward
Age: 27
Unrestricted

Projected 3-Year WARP: 19.6 |   2015-16 RPM: 1.7 | 2015-16 WARP: 6.2

Update (July 1):  Batum has agreed to a five-year, $120 million deal to re-sign with the Charlotte Hornets.

This time a year ago, Blazers fans were clamoring to replace Batum at small forward after he slumped through a disappointing 2014-15 campaign.

After bouncing back in Charlotte and getting more opportunities to show his playmaking ability, Batum now looks like a surefire max player. Although 2015-16 might have been a career year, Batum should still be worth that investment.

8. Jared Sullinger

Boston Celtics
Forward
Age: 24
Restricted

Projected 3-Year WARP: 17.5 |   2015-16 RPM: 3.7 | 2015-16 WARP: 5.2

At age 23 (he turned 24 in March), Sullinger started 73 games for a team that won 48 games and played better with him on the court. He's a terrific defensive rebounder who provides a modicum of floor spacing and is a good passer for a big man. As a result, he ranked 33rd in the league in RPM.

There's reason for concern, certainly. Sullinger's weight could prove an increasing issue as he ages, and since he struggles to defend on the perimeter or protect the rim, he couldn't stay on the court in the playoffs against the Atlanta Hawks. That last impression will be tough for Sullinger to shake this summer.

Nonetheless, a team could do worse than try to pry Sullinger away from the Celtics with an offer in the $10 million-15 million range per year.

9. Dirk Nowitzki

Dallas Mavericks
Forward
Age: 38
Unrestricted

Projected 3-Year WARP: 17.1 |   2015-16 RPM: 2.5 | 2015-16 WARP: 6.6

Three-year projections are meaningless with Nowitzki, who will probably re-evaluate his future annually going forward.

At age 37, Nowitzki remained a fearsome offensive weapon because defenders must stay close to prevent him from picking them apart with his jumper. And while defending quicker opponents is increasingly challenging, Nowitzki should remain valuable offensively until he decides to retire.

10. Pau Gasol

Chicago Bulls
Forward
Age: 35
Unrestricted

Projected 3-Year WARP: 16.2 |   2015-16 RPM: 4.1 | 2015-16 WARP: 10.8

An All-Star each of the past two seasons, Gasol has seen virtually no slippage in his box-score stats deep into his 30s. In fact, he rebounded at a career-high rate each of the past two seasons.

Gasol is more problematic defensively since he almost never forces turnovers, and his teams tend to rebound worse with him on the court. As a result, consider me skeptical of his lofty defensive RPM.

11. Chandler Parsons

Dallas Mavericks
Forward
Age: 27
Unrestricted

Projected 3-Year WARP: 15.1 |   2015-16 RPM: 0.3 | 2015-16 WARP: 3.8

Update (July 1):  Parsons agreed to a  four-year maximum contract with the Memphis Grizzlies worth a projected $94.8 million.

After a slow start following knee surgery, Parsons was playing more or less at his usual standard when another surgery on his right knee ended his season.

Provided Parsons' knee holds up, at 27, we can probably expect him to play at this level through his next contract. And since Parsons is still in the lowest category of maximum salary, that production should be worth the max.

12. Marvin Williams

Charlotte Hornets
Forward
Age: 30
Unrestricted

Projected 3-Year WARP: 14.7 |   2015-16 RPM: 3.0 | 2015-16 WARP: 8.8

Update (July 2):  Williams agreed to a four-year, $54.5 million deal with the Hornets.

It took a decade, but last season, Williams finally realized the potential that made him the No. 2 overall pick in the 2005 draft, emerging as a premier combo forward. Making 40 percent of his 3-point attempts was a big part of that and is unlikely to continue.

However, Williams' defensive versatility allows him to guard power forwards and most small forwards, and that should remain a calling card. Per NBA.com/Stats, the Hornets were 4.7 points better per 100 possessions with Williams on the court last season, the team's best net plus-minus.

13. Dwight Howard

Houston Rockets
Center
Age: 30
Unrestricted

Projected 3-Year WARP: 14.5 |   2015-16 RPM: 0.6 | 2015-16 WARP: 7.1

Update (July 1):  Dwight Howard has agreed to a three-year, $70.5 million deal with the Atlanta Hawks.

As maligned as Howard was during the Rockets' disappointing season, he shot a career-high 62 percent from the field while blocking shots and rebounding at his typical levels.

No, Howard is no longer a feared rim protector. And he continues to carp for opportunities in the post that the results don't justify (per player-tracking data, he averaged .77 points per chance in the post, putting him in the bottom three among players with at least 300 post-ups).

And I certainly wouldn't want to pay him anywhere near his $31 million max or for multiple seasons at age 30.

That all said, as a roll man and defender, Howard could help a lot of teams.

14. DeMar DeRozan

Toronto Raptors
Guard
Age: 26
Unrestricted

Projected 3-Year WARP: 13.9 |   2015-16 RPM: 0.2 | 2015-16 WARP: 7.5

Update (July 1):  DeMar DeRozan has agreed to re-sign with the Toronto Raptors for five years, $139 million-plus.

Public opinion on DeRozan might have overcorrected during Toronto's playoff run. While I was skeptical of DeRozan's All-Star candidacy, his ability to create shots is valuable so long as he can make them with average efficiency as he did during the regular season (.550 true shooting percentage).

Using WARP, DeRozan is likely to remain a 4-5 win player for the next three to four seasons, which puts his value in the neighborhood of his max salary.

15. Luol Deng

Miami Heat
Forward
Age: 31
Unrestricted

Projected 3-Year WARP: 12.8 |   2015-16 RPM: 1.2 | 2015-16 WARP: 5.4

Update (July 2) : Luol Deng has agreed to a four-year, $72 million deal with the Los Angeles Lakers.

Deng revitalized his career in moving to power forward after Chris Bosh was sidelined. Before the All-Star break, Deng averaged 12.1 points and 5.4 rebounds per 36 minutes on .539 true shooting. Those numbers skyrocketed to 16.0 points, 8.6 rebounds and .561 true shooting thereafter, as Deng was able to get by slower defenders. His shooting also went from a minus to a plus.

Teams signing Deng as a pure wing might be disappointed. Teams signing him as a combo forward or a pure 4 will be getting a game-changer.

16. Evan Fournier

Orlando Magic
Guard
Age: 23
Restricted

Projected 3-Year WARP: 12.8 |   2015-16 RPM: -1.1 | 2015-16 WARP: 3.2

Update (July 1):  Fournier agreed to a five-year, $85 million contract extension with the Orlando Magic.

At age 23, Fournier established himself as a full-time starter just as he hit the market as a restricted free agent. Fournier wasn't dramatically better in any one category last season, but he shot more 3s, made them at a slightly better clip and was also more accurate inside the arc (the last one looks the most fluky).

The net result was an efficient scorer without any major weaknesses, which could be enough to earn Fournier a max offer sheet.

17. Bradley Beal

Washington Wizards
Guard
Age: 22
Restricted

Projected 3-Year WARP: 12.5 |   2015-16 RPM: -2.3 | 2015-16 WARP: 2.2

Update (July 1):  Beal agreed to a  maximum five-year contract approaching $130 million with the Washington Wizards.

There are two different Beals: the one who has taken modest steps forward in the regular season throughout his career, peaking last season with the best efficiency of his career, and the one who starred in the 2014 and 2015 playoffs.

Playoff Beal has set the bar unfairly high for regular-season Beal, who's still on track to be a solid player at age 23. However, recurrent stress injuries threaten that progress, and Beal said during the season his minutes might always have to be limited to manage his health. So a long-term deal for him will be something of a risk.

18. Cole Aldrich

L.A. Clippers
Center
Age: 27
Unrestricted

Projected 3-Year WARP: 11.3 |   2015-16 RPM: 3.2 | 2015-16 WARP: 4.1

Update (July 3):  Aldrich agreed to a three-year, $22 million deal with the Minnesota Timberwolves.

Quietly, Aldrich enjoyed an incredible season backing up DeAndre Jordan in 2015-16. According to Basketball-Reference.com, he and Whiteside were the only two players in the NBA to average better than 12 points per 36 minutes (14.8), 12 rebounds per 36 minutes (13.0) and three blocks per 36 minutes (3.1). None of those numbers were far off Aldrich's career marks, and he also shot nearly 60 percent from the field.

Such an impressive performance doesn't always translate into larger minutes. Still, I'd love to see Aldrich get a chance to try it.

19. J.R. Smith

Cleveland Cavaliers
Guard
Age: 30
Unrestricted

Projected 3-Year WARP: 10.0 |   2015-16 RPM: 0.7 | 2015-16 WARP: 3.1

While you're reading this, Smith is celebrating an NBA championship, probably shirtless.

Smith was a key contributor to the Cavaliers' title run, making 200-plus 3s during the regular season at a 40 percent clip. Only the Splash Brothers made more 3s in the playoffs. Best of all for Smith, who had to settle for a modest deal from Cleveland last summer, the Cavaliers have no good way to replace him.

Like Tristan Thompson a year ago, Smith holds all the leverage, which could lead to a crazy deal for him, as I found out during the Dunc'd On mock offseason.

20. Ryan Anderson

New Orleans Pelicans
Forward
Age: 28
Unrestricted

Projected 3-Year WARP: 9.0 |   2015-16 RPM: -0.5 | 2015-16 WARP: 4.8

Update (July 2):  Anderson agreed to a four-year, $80 million deal with the Houston Rockets.

Though he's just 28, Anderson's game doesn't project to age particularly well as he moves toward 30. That squares with his track record of injuries and declining performance.

So while Anderson was more valuable last season than some of the players above him on the list, that might not be the case going forward.

21. Matthew Dellavedova

Cleveland Cavaliers
Guard
Age: 25
Restricted

Projected 3-Year WARP: 8.9 |   2015-16 RPM: 0.9 | 2015-16 WARP: 0.3

Update (July 1):  The Milwaukee Bucks extended a four-year, $38.5 million offer to Dellavedova. Starting July 7, the Cavaliers will have three days to match (though they aren't expected to do so).

Dellavedova opted to play last season on a one-year qualifying offer and take his chances again this summer. That gamble should pay off.

Before he was a non-factor in the Finals, Dellavedova had the best season of his career, seeing his 3-point percentage bounce back from 30 percent to 40 percent. Add in his physical defense and Dellavedova is a good fit for teams who get ball handling from the wing.

22. Bismack Biyombo

Toronto Raptors
Center
Age: 23
Unrestricted

Projected 3-Year WARP: 8.9 |   2015-16 RPM: 0.0 | 2015-16 WARP: 4.1

Update (July 2):  Biyombo agreed to a four-year, $70 million deal with the Orlando Magic.

Biyombo took full advantage of Jonas Valanciunas' injury to showcase his ability as a starter during the playoffs, and likely earn a starting job somewhere else next season -- along with a huge raise from last year's $2.8 million salary.

Because he's such a limited offensive threat, and because his rebounding in the playoffs was above his career norms, Biyombo doesn't project as a max-caliber player. His value lies more in the $15 million-20 million range.

23. Deron Williams

Dallas Mavericks
Guard
Age: 32
Unrestricted

Projected 3-Year WARP: 8.8 |   2015-16 RPM: 0.1 | 2015-16 WARP: 2.6

Update (July 4):  Williams agreed to a one-year, $10 million deal with the Mavericks.

After taking a buyout in Brooklyn and signing in Dallas, Williams rebuilt his value.

Though his performance wasn't much better than it had been, there weren't the same kind of concerns about Williams in the locker room. He opted for free agency again and should easily beat the $5.4 million he made from the Mavericks last season.

24. Zaza Pachulia

Dallas Mavericks
Center
Age: 32
Unrestricted

Projected 3-Year WARP: 8.2 |   2015-16 RPM: 2.4 | 2015-16 WARP: 4.0

Before the All-Star break, Pachulia was a revelation for Dallas, averaging a double-double. His productivity fell off thereafter and Pachulia lost his starting job for stretches.

The minutes Pachulia played -- nearly 30 minutes a game -- might have been the issue. He hadn't played so many minutes per game in a decade. In a smaller role, Pachulia should remain effective.

25. Ian Mahinmi

Indiana Pacers
Center
Age: 29
Unrestricted

Projected 3-Year WARP: 8.0 |   2015-16 RPM: 2.1 | 2015-16 WARP: 4.1

Update (July 2): Mahinmi agreed to a four-year, $64 million deal with the Washington Wizards.

At the age of 29, Mahinmi got his first opportunity to start in the NBA after the Pacers dealt incumbent center Roy Hibbert and responded with the best season of his career. While not the rim protector Hibbert was, Mahinmi is more mobile defensively, and ranked fifth in the league in defensive RPM. Mahinmi also proved a surprisingly important cog in the Indiana offense, boosting both his usage rate (15.7 percent) and 2-point accuracy (58.9 percent) to the best marks of his career as a rotation player.