The Houston Rockets’ return to the ranks of the league’s top teams has been one of the biggest stories of the season so far. Now, though, James Harden, Mike D’Antoni and company will have to weather the loss of one of the most important parts of their early-season resurgence until well into 2017.

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D’Antoni told reporters on Monday that center Clint Capela was slated to have an MRI exam on his left knee, and that he would miss Houston’s Tuesday matchup with the San Antonio Spurs. The Rockets’ starting center exited Saturday night’s game against the Minnesota Timberwolves with 10:16 remaining in the third quarter, after banging knees with Wolves sophomore Karl-Anthony Towns:

Capela wouldn’t return, finishing with 10 points and four rebounds in 15 minutes of playing time. The Rockets would hold on for a 111-109 overtime win, their 10th straight victory, behind 28 points apiece from Harden and Ryan Anderson, as well as 20 points, six rebounds, four assists and two steals off the bench by Eric Gordon.

After multiple reports on Monday night indicated Capela had suffered a significant injury, Adrian Wojnarowski of The Vertical confirmed Tuesday morning that the Swiss national is expected to be sidelined for up to a month and a half:

Shortly thereafter, the Rockets made it official:

For his part, Capela seems confident he’ll be back to full strength on the early side of the injury timetable, according to a chat with Mark Berman of Houston FOX affiliate KRIV-TV:

A four-to-six-week timetable would put Capela on the shelf for between 15 and 24 games. The 22-year-old might not be a household name, but losing him for such a significant stretch could pose a huge problem for a Rockets team that has come to rely heavily on Capela’s talents on both ends of the floor.

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Houston didn’t exactly pull out all the stops to keep Dwight Howard in free agency this summer, in large part because Daryl Morey and company believed the 6-foot-10, 240-pound Capela was ready and able to step into a larger role as the Rockets’ primary pick-and-roll dive man and space-eating rim protector. So far, so good: Capela has averaged 11.8 points, eight rebounds and 1.6 blocks in 24.5 minutes per game this season, shooting a sparkling 64 percent from the field, the third-highest field-goal percentage in the NBA.

Capela has proven an imposing presence in the paint. Opponents have shot 46.6 percent on attempts at the rim with Capela defending, the 13th-best mark in the NBA among players to face at least a handful of up-close shots per night, according to SportVU player tracking data. Quiet as it’s kept, though, his absence might be felt even more on the offensive end.

Through the first two months of the season, Capela has emerged as one of the NBA’s most efficient and effective dive men in the pick-and-roll. He has averaged 1.3 points per possession used as the roll man in the screen game, according to Synergy Sports Technology’s game-charting data, the 11th-best mark among players who have finished at least 25 such plays, and he has scored on must over two-thirds of the pick-and-roll plays he’s finished with a shot attempt, foul drawn or turnover, which trails only hard-working behemoth finishers DeAndre Jordan, Rudy Gobert and Tristan Thompson, and emerging Toronto Raptors reserve Lucas “Bebe” Nogueira.

Capela’s combination of relentless rolling, athleticism to go up and get the ball, and gift for finishing through contact have made him a perfect pick-and-roll partner for Harden, who has directly assisted on 84 of Capela’s 151 made shots (55.6 percent). His rim-running demands defensive attention, which helps provide an organizing principle for Houston’s half-court attack.

The extra step or two that a help defender has to sag in to check Capela’s roll gives shooters like Anderson, Gordon and Trevor Ariza that much more room and time to rise and fire when the ball swings their way, and gives Harden an almost unfair amount of options from which to pick in slicing and dicing defenses, as SB Nation’s Mike Prada recently broke down:

D’Antoni will look to veteran power forward/center Nene, young bull Montrezl Harrell and just-recalled-from-the-D-League rookie Chinanu Onuaku to plug the gap. Asked Monday if his game plan at the five spot would change with Capela out, the Rockets’ head coach told reporters, “Just somebody else doing it.”

None of those options provides the same shot-blocking threat or rim-rolling menace as Capela, though. Peerless on-ball pest Patrick Beverley is probably the Rockets’ best defensive player, but in terms of total on-court impact, Capela might be Houston’s second-most-important piece behind Harden.

That said, the Rockets have recently figured out how to stay afloat when Harden hits the bench. Betting against the Beard and the ex-‘Stache to figure out how to navigate the loss of Capela’s 25 minutes per night might be foolhardy.

For one thing, I’d expect D’Antoni to give lineups without a center — think Anderson or Sam Dekker at the five — a longer look when matchups allow for it. Your standard small-sample size alert applies, but such super-small-ball lineups are a +23 in 34 minutes thus far this season, according to NBA.com’s lineup data, and it wouldn’t exactly be off-brand for D’Antoni to downsize if he thinks Houston’s got a chance to win by damning the torpedoes and bombing away. After all, he did just that on Saturday night, riding the Anderson-Ariza-Gordon-Beverley-Harden group to come back on and take out the Wolves after Capela went out.

But doing that for one night against an overwhelmed young team is one thing; doing it for a month and a half against a slate that includes at least a dozen teams presently in playoff position, including six meetings with fellow Western powers San Antonio, Memphis, the Clippers and the Warriors, might be another. In times like these, it’s awful nice to have 21 banked wins and an MVP point guard, but still: how well Houston navigates Capela’s stint on the injured list could wind up determining whether the Rockets host their opening-round playoff series, as they did two seasons ago en route to a Western Conference finals berth, or open up on the road, as they did last year before making a hasty exit from the postseason in Round 1.

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Dan Devine is an editor for Ball Don’t Lie on Yahoo Sports. Have a tip? Email him at devine@yahoo-inc.com or follow him on Twitter!

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