BOSTON (CBS) — The Celtics may be without Marcus Smart for a second straight game on Tuesday night.

It’s likely that Brad Stevens won’t have his best defender when the Celtics host the New York Knicks at TD Garden, as Smart is listed as questionable with a sprained left ankle. Smart suffered the injury in Boston’s home opener last Wednesday, forcing him to miss Friday night’s win in Philadelphia, and did not practice with the team on Monday.

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With Stevens juggling his lineups after Gordon Hayward’s devastating injury on opening night, Smart was in Boston’s starting five last Wednesday. He played 32 minutes and racked up 12 points off of 4-for-13 shooting to go with seven rebounds and four assists in the 108-100 Boston loss.

With Smart sidelined on Friday, Stevens went with a bigger starting five with Aron Baynes, while reserve guard Terry Rozier saw 30 minutes of action off of the bench alongside Kyrie Irving in the Boston backcourt.

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The Knicks may be 0-2 on the young season, but Boston will need all the defensive help they can get with Kristaps Porzingis putting up some gaudy numbers to start his third NBA season. The 7-foot-3 forward is averaging 32 points per game off of 49 percent shooting, one of the few bright spots for the lowly Knickerbockers.

Despite giving up nearly a foot in height, Smart has given Porzingis defensive fits in the past. It’s an interesting matchup whenever it plays out (one Porzingis said made him change his game on Tuesday), but New York’s giant may not have to worry about that on Tuesday night. That will just put more defensive pressure on the rest of Boston’s roster as they look to improve to .500 on the season.

Tune in to Tuesday night’s Celtics-Knicks matchup on 98.5 The Sports Hub — the flagship station of the Boston Celtics. Pregame coverage with Sean Grande and Cedric Maxwell begins at 7pm!

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