Ranking every NBA playoff series by upset potential
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Compared to the one-and-done format of the NCAA tournament, of course, the NBA's playoff system is unforgiving to underdogs. Not only do they have to beat the higher-seeded team four times, they must win at least once on the road.
Despite those edges for favorites, we should expect to see several upsets in the 15 NBA playoff series to come between now to late June.
Let's take a look at the potential for surprises in this year's first round.
With the help of a formula that looks at the historical odds of winning a playoff series based on the two teams' point differential during the regular season along with the results of the head-to-head season series, here are the eight matchups in order from most unpredictable to most set in stone.
1. Miami Heat (3) vs. Charlotte Hornets (6)
Teams like Miami with home-court advantage but a weaker point differential than their opponent are just 16-13 since 2003. And in the only meeting of the two teams after Chris Bosh went out of the lineup at the All-Star break, the Hornets went into American Airlines Arena and came up with a 109-106 victory.
Charlotte has yet to win a playoff game since returning to the NBA via expansion in 2004. That could change in a big way here.
Upset probability: 46 percent
2. Atlanta Hawks (4) vs. Boston Celtics (5)
If the Celtics lose this series, they can blame the Hawks -- but not in the way you might think. Had Atlanta merely won Wednesday's season finale against a Washington Wizards team playing without guards John Wall and Bradley Beal, Boston would have been the fourth seed and had home-court advantage against a Miami team the Celtics swept 3-0, making them overwhelming favorites.
Instead, Boston must go on the road to face Atlanta, which won the season series 3-1, including a 118-107 victory last Saturday at home that secured the head-to-head tiebreaker. The Hawks also have been the better team in terms of point differential over the course of the season, though the margin is close enough that the Celtics have a real chance of pulling the upset.
Upset probability: 31 percent
3. Cleveland Cavaliers (1) vs. Detroit Pistons (8)
The Pistons' chances are inflated slightly by winning the regular-season finale between the two teams, who both rested their starters. Detroit outlasting a 36-point effort from Jordan McRae doesn't really tell us much about what the playoff series will look like.
Nonetheless, the Pistons won a pair of more competitive games against the Cavaliers, including a 96-88 victory in the only game with midseason addition Tobias Harris in the lineup.
Harris, Marcus Morris and Stanley Johnson give Detroit a variety of athletic forwards with enough size to defend LeBron James, who went 5-of-18 with six turnovers in the February matchup. Cleveland is still the sizable favorite, but this could be a relatively tricky 1-8 matchup.
Upset probability: 28 percent
4. Toronto Raptors (2) vs. Indiana Pacers (7)
The last thing anyone in Toronto wants to hear is the word "upset" after two consecutive years getting knocked off in the opening round despite home-court advantage. The good news is this Raptors team is better than its two predecessors, and also boasts more playoff experience -- a factor in upsets, if an overrated one -- after those runs and the addition of DeMarre Carroll.
Toronto also won the season series 3-1, though that slightly overstates the one-sidedness of the matchup. The Raptors' win in Indiana came in overtime (one of seven OT losses without a win for the Pacers), and Indiana's lone victory (by 16 points) was the most lopsided of the four games.
Upset probability: 21 percent
5. Los Angeles Clippers (4) vs. Portland Trail Blazers (5)
It's only fitting given the depth of the respective conferences that every East series has a better projected chance of an upset than any in the West. If someone is going to knock off one of the West's top four teams, it will likely be the Blazers, who firmly established themselves as the best of the rest since the start of February.
Portland and L.A. have developed a bit of a rivalry, including a preseason flare-up between head coaches Doc Rivers and Terry Stotts. It didn't help that the Clippers were on the other side when the Blazers accidentally left C.J. McCollum off their active list for a January matchup. The Clippers won against McCollum-less Portland, but still needed a second-half comeback at home in late March to win the season series 3-1.
Upset probability: 18 percent
6. Oklahoma City Thunder (3) vs. Dallas Mavericks (6)
After Blazers-Clippers, the shots become increasingly long for other West teams to knock off the favorites. Since 2003, the biggest upset in terms of point differential was the 2007 Warriors over the Mavericks (the third time a No. 8 seed upset a No. 1, and first under the best-of-seven format). Dallas' differential was 7.6 points per game better than Golden State's -- identical to the margin between the Thunder and Mavericks this year.
It's worth noting that the three biggest upsets in that span by point differential (Atlanta over Orlando in 2011 and Memphis over Russell Westbrook-less Oklahoma City in the 2003 conference semifinals) all came when the lower-seeded team had won the season series. And that's where the news goes from bad to worse for the Mavericks, who got swept 4-0, albeit with a couple of close losses.
Upset probability: 1.1 percent
7. Golden State Warriors (1) vs. Houston Rockets (8)
Believe it or not, the 73-win Warriors actually aren't the favorite least likely to get upset. At some point, we're splitting hairs -- the model suggests 250-1 odds against a Rockets upset -- but Houston is a tad friskier than the other bottom seeds in the West.
The Rockets secured their playoff spot with three consecutive wins by 20-plus points, finally living up to the potential that had them considered contenders before the season. (Those three wins pushed their point differential into positive territory for the first time all season.)
That noted, Houston hasn't been particularly competitive with a full-strength Golden State. The Warriors trounced the Rockets by 20 in Houston in the first meeting after last year's Western Conference finals victory and also won on the road without the injured Stephen Curry on New Year's Eve, sweeping the season series 3-0.
Upset probability: 0.4 percent
8. San Antonio Spurs (2) vs. Memphis Grizzlies (7)
The Grizzlies are officially in "so you're telling me there's a chance" territory. Playing without starters Mike Conley and Marc Gasol, along with a list of reserves too long to name here, Memphis has been outscored by 4.7 points per game since the All-Star break and heads to the postseason with just one win in its past 11 games.
During that stretch, the Spurs won both ends of a home-and-home matchup against the Grizzlies without the injured Kawhi Leonard, completing a sweep of the season series. If Memphis can take a game off San Antonio in the postseason, the Grizzlies will have overachieved.
Upset probability: 0.1 percent
