How good can these Lakers be with LeBron out?

Can the Los Angeles Lakers keep up their competitive play without LeBron James if he's indeed sidelined by a groin injury longer than initially indicated, as they are preparing for according to a report Thursday by ESPN's Brian Windhorst and Adrian Wojnarowski?

After LeBron left the Lakers' showdown with the two-time defending champion Golden State Warriors on Christmas Day, L.A. pulled away behind the strong play of Rajon Rondo and Ivica Zubac for an improbable blowout victory.

While that was an extreme example, all season long the Lakers have been more effective offensively without James than any of his other recent teams. Can the Lakers maintain that success over an extended stretch? Let's take a look at some reasons for optimism and concern.

Other Lakers stepping into spotlight

Naturally, with LeBron off the court there are a lot more possessions to go around for his teammates. So it's unsurprising that all nine Lakers who have played at least 100 minutes this season both with and without James have increased their usage rates in his absence, according to NBAwowy.com.

Brandon Ingram sees the biggest change in his role with LeBron on the bench, using more than 30 percent of the team's plays as compared to barely more than league average (20 percent) when playing with LeBron. Lance Stephenson, Lonzo Ball and Kyle Kuzma also see sizeable jumps.

Unlike James' 2017-18 Cleveland team, stocked with role players dependent on LeBron to create opportunities for them, this year's Lakers were built with more ballhandlers and shot creators, and they have thrived without James. As a result, the Lakers haven't dropped off nearly as much offensively as LeBron's teams have historically.

The stats pages on Cleaning the Glass show a player's net impact on offensive rating (on-court minus off-court) each year, as well as the percentile for that difference among all players. James' net offensive impact has ranked in the 95th percentile or better each of the last seven seasons, dating back to his first year with the Miami Heat. LeBron's offensive impact that season, still better than 82 percent of all NBA rotation players, had been the worst of his career. This year, it's down to the 43rd percentile, as the Lakers are actually scoring slightly more efficiently with James on the bench.

In part, that reflects how the Lakers aren't as well-equipped to support James as his past teams. The Lakers are scoring only slightly better than league average with LeBron on the court, a massive change from Cleveland teams that were elite offensively any time he played. But L.A.'s above-average offense without James is also unusual. The last LeBron team to score so efficiently with him on the bench was the 2010-11 Heat, who featured a late-prime Dwyane Wade and a prime Chris Bosh.

That's good news for the Lakers in James' absence ... if they can maintain it.

Lakers shooting unsustainably well without LeBron

Looking closer at the differences in player shooting with and without James shows the improved efficiency is due largely to 3-point shooting. The Lakers, maligned this summer for having too little outside shooting, are making 38.1 percent of their 3s with LeBron on the bench, according to NBA Advanced Stats, as compared to 33.1 percent with him on the court. Much of that improved accuracy appears unsustainable.

Ingram, for example, has shot largely the same percentage on 2s with and without LeBron on the court. The difference in his true shooting can be traced largely to shooting 7-of-9 (78 percent) from 3-point range when James sits as compared to 6-of-33 (18 percent) when he plays. It's not realistic for Ingram to keep shooting so well on 3s. The same is true of Rondo's 61.5 percent 3-point shooting without LeBron (8-of-13) and even Stephenson's 39.5 percent accuracy on a much larger 61 attempts (he's a career 31 percent shooter).

Further confirmation that the Lakers' shooting without James is unsustainable comes from Second Spectrum tracking. While the Lakers' effective field-goal percentage (eFG, which counts 3s as 1.5 field goals to reflect their added value) drops only from 54.1 percent when LeBron plays to 53.5 percent when he sits, their shot quality is much worse.

According to Second Spectrum's quantified shot quality measure, which estimates the eFG for an average player on the same shots given their distance, type and location of nearby defenders, the Lakers' shot quality drops from 53.6 percent with James to 51.9 percent without him. And when we also factor in the ability of the shooter using Second Spectrum's quantified shot probability measure, that gap grows from 54.1 percent when LeBron plays (identical to the team's actual eFG in those minutes) to 50.1 percent when he sits -- a shot quality that would rank 27th among the NBA's 30 teams this season, reflecting one of the league's weaker offenses.

Hot shooting has helped the Lakers stay afloat without James so far this season, but it doesn't look like a good indicator of how they'll perform if he misses several games due to his groin injury.

Playoff impact of LeBron's absence

After beating the Warriors on Christmas, the Lakers are now just 2.5 games back of No. 1 Golden State in the standings and tied with the LA Clippers for fourth in the Western Conference. However, with five other teams two games back or fewer, the Lakers aren't assured a playoff berth. Simulations using ESPN's Basketball Power Index show the Lakers making it a little more than 80 percent of the time, while FiveThirtyEight's projections give them a 65 percent chance of reaching the postseason.

During a season where a few games could be the difference between home-court advantage in the first round and missing the playoffs entirely, how well the Lakers can navigate an extended James absence could have outsized impact on their final finish. And that makes it crucial for the Lakers to keep up the hot shooting that has helped them thrive without LeBron so far.