Portland Trail Blazers guard CJ McCollum has been diagnosed with a collapsed right lung and will be sidelined indefinitely, the team said Tuesday.

McCollum was injured in the final quarter of the Blazers' 145-117 loss to the Boston Celtics on Saturday. He was listed as probable with a rib contusion for Monday night's game against the Los Angeles Clippers, but did not play in the 102-90 loss.

McCollum's condition was revealed by a CT scan, the team said.

Portland Trail Blazers guard CJ McCollum, right, drives against Boston Celtics forward Grant Williams during the second half of an NBA basketball game in Portland, Ore., Saturday, Dec. 4, 2021. The Celtics won 145-117. (AP PhotoSteve Dipaola)

Portland Trail Blazers guard CJ McCollum, right, drives against Boston Celtics forward Grant Williams during the second half of an NBA basketball game in Portland, Ore., Saturday, Dec. 4, 2021. The Celtics won 145-117. (AP PhotoSteve Dipaola)

He is averaging 20.5 points, 4.1 rebounds and 4.5 assists this season.

McCollum's injury is one of several to befall the struggling Blazers. All-Star Damian Lillard has missed four games with lower abdominal tendinopathy. Backup point guard Anfernee Simons is out with a right ankle sprain, while forward Nassir Little has missed four games with a left ankle sprain.

Guard Ben McLemore left the game against the Clippers with a bruised hip. Center Cody Zeller has a bruised right quad.

Portland Trail Blazers guard CJ McCollum, left, dribbles past San Antonio Spurs guard Dejounte Murray during the second half of an NBA basketball game in Portland, Ore., Thursday, Dec. 2, 2021. (AP PhotoCraig Mitchelldyer)

Portland Trail Blazers guard CJ McCollum, left, dribbles past San Antonio Spurs guard Dejounte Murray during the second half of an NBA basketball game in Portland, Ore., Thursday, Dec. 2, 2021. (AP PhotoCraig Mitchelldyer)

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