John Wall has already missed 10 games this season dealing with persistent soreness in his left knee. He’s about to miss an awful lot more.

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After Wall missed the Washington Wizards’ Saturday win over the Atlanta Hawks due to knee trouble, Ben Standig of FanRag Sports reported that multiple sources indicated “a concern the absence may end up quite a bit longer.” Those fears were confirmed on Tuesday morning by Candace Buckner of the Washington Post, who reported that Wall will undergo a “clean-up” procedure on the bothersome knee that is expected to keep him out for six to eight weeks.

In the short term, that means Wall won’t participate in next month’s 2018 NBA All-Star Game, where he was set to make his fifth straight appearance as a coach-selected reserve drafted to LeBron James’ team. Wall now becomes the second All-Star taken off the board due to injury, joining friend and former Kentucky teammate DeMarcus Cousins, who ruptured his Achilles tendon this weekend. NBA Commissioner Adam Silver named Oklahoma City Thunder forward Paul George to replace Cousins; who he’ll tab to head to L.A. in Wall’s stead remains to be seen. (Candidates include Detroit Pistons center Andre Drummond, Philadelphia 76ers rookie Ben Simmons, Charlotte Hornets point guard Kemba Walker and Miami Heat point guard Goran Dragic.)

Looking to games that matter, though, Wall’s injury deals a major blow to the Wizards’ chances of making a fourth playoff trip in five years. It also must send shivers down the spines of Washington’s front office, which forked over a four-year, $170 million extension to retain Wall this past summer despite multiple prior knee issues, including 33 games lost to a “stress injury” in 2012-13, and a pair of other “clean-up” surgeries on his knees during the summer of 2016.

Coming on the heels of reports that player and team “have no answers as to why he periodically deals with knee soreness” that comes and goes, resulting in him needing his knee drained “a few times” in recent months and leaving him looking like a superhero on some nights and a sidekick on others, the Wizards must now have at least some level of concern about ongoing knee woes turning a 27-year-old cornerstone into a 30-year-old millstone.

Washington enters Tuesday’s action at 27-22, just 1 1/2 games behind the Heat for the No. 4 spot in the East. They’re also only two games up on the No. 8 Sixers and 4 1/2 games ahead of ninth-place Detroit, who just added a five-time All-Star of its own in an attempt to save a spiraling season.

The Wizards are no stranger to such moves, having flipped first-rounders for immediate help — Bojan Bogdanovic last year, Markieff Morris in 2016, Marcin Gortat in 2013 — several times in recent years. For now, according to NBA.com’s David Aldridge, Washington is resisting the urge to put another future No. 1 on the table to tide the Wiz over in Wall’s absence … unless, of course, a “star” becomes involved before the Feb. 8 trade deadline, leaving more than a week for things to get weirder in the league, and for things to get worse in D.C. And they probably will:

A six-to-eight-week timeline would put Wall on the shelf for about 20 to 25 games, with 16 of the Wizards’ next 20 coming against opponents with winning records. Some of those opponents might matter more than others.

The Wizards will play their final two regular-season games against the eighth-seeded Sixers (with whom they’ve split their first two) in February. They’ll play all three of their games against the seventh-seeded Indiana Pacers between now and St. Patrick’s Day. They’ve got their final game of the year against the fifth-seeded Milwaukee Bucks on Feb. 27, needing a win to avoid handing Giannis Antetokounmpo a head-to-head tiebreaker.

Washington’s already won its season series with Detroit, which helps, and barring some drastic additions, it seems unlikely that the 22-28 New York Knicks or 20-29 Hornets will be poised to make a leap up the standings. But Scott Brooks will have to lead his team into a handful of very important games, contests that could be crucial for tiebreakers and postseason positioning, without the franchise’s signature star and top playmaker.

Really, the Wizards have been without Wall — the real John Wall — for most of the year, ever since he suffered a knee-to-knee collision during an early November game against the Dallas Mavericks. Wall continued to play through his discomfort, but the pain and swelling eventually led the team to shut him down for several weeks to have platelet-rich plasma treatment and viscosupplementation injections aimed at nursing the balky knee back to health.

Wall returned to the court on Dec. 13, and has shown flashes of his familiar elite form — a string of double-digit assist nights around Christmas, consecutive 30-plus-point performances earlier this month. In the main, though, Wall has generally looked a bit less than what we’ve come to expect, averaging 18.6 points, 9.3 assists, 3.7 rebounds, 1.5 steals and 1.1 blocks in 34.2 minutes per game since his return while shooting just 40.5 percent from the floor.

Amid Wall’s recession, running buddy Bradley Beal has posted the best season of his pro career, earning his first ever All-Star nod for his work as the Wizards’ leading scorer. The silver lining for Wizards fans: Beal’s still around to carry the load, and Washington has been able to tread water without Wall this season, going 6-6 in his 12 total absences.

There’s a gray cloud there, though. As well as Beal has played this year, he hasn’t been able to carry the Wizards by himself without Wall riding shotgun. When they share the floor, Washington has outscored opponents by 148 points in 1,164 minutes this season, per NBA.com; when Beal’s played without Wall, the Wiz have barely broken even, going +2 in 599 minutes.

Even without looking quite like himself, with Wall on the floor, the Wizards have outscored opponents by 4.3 points per 100 possessions, equivalent to the Boston Celtics’ fourth-best-in-the-NBA full-season net rating. They’ve been outscored by 1.9 points-per-100 with him off it, a bottom-10 mark. When Wall has played, the Wizards have scored like a top-five offense and defended like a top-eight defense. With him unavailable, they’ve produced and prevented points at the same levels as the 16-35 Mavericks.

To some degree, this is understandable. Tim Frazier’s a serviceable backup capable of more in spot-start duty, and Tomas Satoransky can offer a steady hand as a combo guard on and off the ball. But expecting much more than that is expecting too much. Wizards fans (and some players) have long called Ernie Grunfeld onto the carpet for the mistakes he’s made in building threadbare benches and ramshackle rotations, but you can’t really ding him for not having a ready replacement for John Wall, because he’s John freaking Wall.

In this case, the efficiency stats bear out what the eye test tells you. While Beal’s great, and Otto Porter’s worth the nine figures he got, and Kelly Oubre’s blossoming, John Wall is what makes the Wizards a playoff team. For the next two months, they’re going to have to act as if without him, lest they find themselves on the outside looking in, and too far gone to make up the distance, by the time he comes back.

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Dan Devine is a writer and editor for Yahoo Sports. Have a tip? Email him at devine@oath.com or follow him on Twitter!

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