Updated

BOSTON -- The Toronto Raptors and Boston Celtics open their February schedules against each other in a midseason game that has double meaning Wednesday night.

And the struggling Raptors will have to do it without All-Star starter DeMar DeRozan.

The teams are fighting it out for first place in the Atlantic Division and second and third in the Eastern Conference, which brings us to the other thing that makes this a big game.

With Tyronne Lue of the Cleveland Cavaliers not eligible to coach because he did it last year, Boston's Brad Stevens and Toronto's Dwane Casey are watching their teams battle it out through Sunday to see which coach will handle the East in the All-Star Game.

The Raptors, winners in overtime at home against the New Orleans Pelicans on Tuesday night, trail the Celtics by a half-game and will be without DeRozan for the fifth time in six games because of a sprained right ankle. He returned and had swelling after Sunday's loss to Orlando and was ruled out for Tuesday and Wednesday.

DeRozan was sixth in the NBA in scoring through Monday, averaging 27.8 points per game, and had 41 in a win over Boston on Jan. 10. The Celtics blew leads in both games and DeRozan had plenty to do with it.

The Raptors won for only the second time in eight games Tuesday as Kyle Lowry, their other star guard, had 33 points, including the winner with 4.3 seconds left in OT, and 10 assists in another rugged display.

"He gets hit more than any All-Star I've ever been around ... he's Philly tough," Casey said of Lowry, joking his player could have been a running back for the Eagles. Lowry got a kick out of that, saying, "Yeah, I would've been really good for that team."

Lowry has three straight 30-point games, the first time he's done that in his career.

Lowry -- and not DeRozan -- will have to deal with Isaiah Thomas, who continues to run up amazing numbers.

Monday night, Thomas scored 24 of his 41 points in the fourth quarter to help his team, still playing without the injured Avery Bradley (Achilles strain), pull out a victory over the Detroit Pistons. The 41 left him one point shy of becoming only the third Celtic to average 33 points during a month.

Only Larry Bird (February, 1988, 33.1) and Paul Pierce (February, 2006, 33.5) pulled off the feat, but Thomas continues to amaze.

"People were saying that to me throughout the day, so I saw that," Thomas said after the game. "I was close but I wasn't trying. I was just trying to do what my team needed me to do."

Asked about being in the same neighborhood as Bird and Pierce, Thomas said: "That doesn't even seem real. It doesn't sound real. So many great players did it before me. To have my name up there with those legends is unbelievable."

It was his 32nd straight game with at least 20 points as he closes in on John Havlicek's club record of 40. He scored fewer than 20 only once this season and had 18 in that game.

Thomas scored at least 20 points in the fourth quarter four times this season while no one else in the league has done it more than once. He has also had a league-high nine 15-point fourth quarters.

In the last 11 home games, Thomas -- averaging 29.1 points per game, second only to Russell Westbrook's 30.8 -- has 396 points in 395 minutes.

Monday's win came in the start of a four-game homestand running through Sunday for Boston.

Both teams play Friday and Sunday, with the Raptors on the road for both.