EL SEGUNDO, Calif. (AP) — DeMarcus Cousins is facing rehab from another major injury, and the Los Angeles Lakers have endured their first big problem of a season with championship expectations.

Cousins was diagnosed Thursday with a torn ACL in his left knee, an injury that could sideline the six-time All-Star big man for much — if not all — of this coming season. Cousins' agent, Jeff Schwartz of Excel Sports Management, said a timeline for surgery is being discussed.

Cousins, who spent last season with Golden State, got hurt earlier this week in a workout in Las Vegas. The ACL tear comes about 18 months after he ruptured his left Achilles tendon, and roughly four months after he tore his left quadriceps muscle during this past season's playoffs.

Those previous injuries cost him a lot of games and a lot of money.

This injury is only going to add to those totals.

"He was going to be a big part of what we're going to do," Lakers forward Kyle Kuzma said after USA Basketball practice at the Lakers' facility on Thursday, shortly after the severity of Cousins' injury was confirmed.

Plenty of players from around the NBA turned to social media to send Cousins messages of support, including Pau Gasol, who wrote "You will come back stronger brother." Golden State coach Steve Kerr — a U.S. assistant — said he was devastated for Cousins. Kerr also pointed out that the two games Golden State won against Toronto in last season's NBA Finals, Games 2 and 5, were not coincidentally games where Cousins played particularly well for the Warriors.

"Injuries are part of the game but when you are talking about a player who has now dealt with the two most feared injuries for NBA players — the Achilles and ACL — each basically knocking you out for an entire season, to deal with that over a 2 ½-, three-year span, it's unheard of," Kerr said. "So I don't know. What a blow for him, for the Lakers. He's going to have to process it all and start all over again."

The Achilles tear preceded Cousins' 2018 trip to free agency, where he could have commanded a multi-year deal exceeding $100 million. He wound up having to sign a one-year, $5.3 million contract with Golden State.

And this summer, again after dealing with injury, Cousins had to settle for much less than the going rate for someone averaging more than 20 points and 10 rebounds per game for his career. He signed with the Lakers on another one-year deal, this time for $3.5 million.

"I've told y'all before I don't take any of this for granted," Cousins said in June, during the NBA Finals when he and the Warriors lost in six games to Toronto. "I've seen how quick this game can be taken away from you. So every chance I get to go out there and play, I'm going to leave it on the floor."

This could have been a massive year for Cousins, who was going to get a chance to play with LeBron James and reunite with his former New Orleans teammate Anthony Davis with the Lakers — a team with major aspirations after an offseason roster overhaul.

A big year could have set Cousins up for a significant contract next summer. It is now unclear if he'll play at all before he returns to the open market.

"It's been a couple years of hell for DeMarcus," Kerr said.

The Lakers, even without Cousins, still figure to have more than enough talent to end a stretch of six consecutive seasons without a playoff berth, by far the longest such run in franchise history.

James returns after an injury-marred season where he averaged 27.4 points, 8.5 rebounds and 8.3 assists. Davis — a six-time All-Star and three-time All-NBA performer — was acquired in a blockbuster trade with New Orleans, JaVale McGee and Rajon Rondo were re-signed and Danny Green chose to sign with the Lakers for two years and $30 million after helping Toronto win the NBA title.

But without Cousins, there is a bit of a void on the Lakers' roster as far as center. Among current Lakers, only Davis and McGee have spent any significant time in their careers at that position.

"It's no joke when you get injured," Kuzma said. "This is our livelihood and is something that we love to do. It's super-unfortunate for a guy like DeMarcus. You can tell how much he loves basketball through all these injuries — he's fought back and tried to get back as early as possible. That's kind of how the ball goes sometimes."

Cousins has averaged 21.2 points and 10.9 rebounds over parts of nine NBA seasons with Sacramento, New Orleans and Golden State. Cousins is one of only 11 players in NBA history to average that many points and rebounds per game in a career, a list that includes two other active players — Minnesota's Karl-Anthony Towns and Philadelphia's Joel Embiid.

"Just feel terrible for him," Kerr said.

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