Celtics point guard Kyrie Irving on Wednesday missed his second consecutive game because of a right knee strain, and since the matchup against the Pistons was Boston’s last before the break, Irving’s absence raised questions about whether he will be able to play in Sunday’s All-Star Game in Charlotte, N.C.

Irving was receiving treatment in the team training room prior to Wednesday night’s game, and coach Brad Stevens said he remains day to day.

“I think that there would be a chance that, if we played Friday or Saturday, that he’d be cleared,’’ Stevens said, “and I guess my thought would be, if he would have been cleared for us on Friday or Saturday, then he should probably play [in the All-Star Game]. If there’s any issues at all and he’s not 110 percent, I would not play.’’

Irving was selected by the fans as an All-Star starter, and then team captain LeBron James selected Irving to join his team for the game. It may make more sense to err on the side of caution even if Irving is cleared to return before Sunday’s game, but Stevens said that it could also offer a chance for Irving to resume some light basketball activities after sitting out for a week.

“You need to get up and down the court,’’ Stevens said. “We can’t do anything, per NBA rules, until mid-next week when we get back together. To me it makes sense, but if he’s 100 percent. He’s got to be 100 percent. But I haven’t heard, because I haven’t really asked.’’

Point guard Terry Rozier and forward Robert Williams missed Wednesday’s game because of illness.

Fine mess

76ers star Joel Embiid on Wednesday was fined $25,000 for “public criticism of the officiating’’ following his team’s loss to the Celtics on Tuesday. As Embiid finished his news conference after the game, he leaned into the microphone and said, “The referees [expletive] sucked.’’

The officials’ Last Two Minute Report from Tuesday’s game showed several incorrect calls in the final moments. The report said that Al Horford should have been whistled for fouling Embiid with 33.9 seconds left and Boston leading, 106-104.

The report also stated that Celtics forward Jayson Tatum should not have been called for a foul on Jimmy Butler’s 3-point play that made it 108-107 with 16.1 seconds left, and that Horford should have been called for a travel on the play that followed.

Must-see TV

Former Celtics point guard Isaiah Thomas made his season debut with the Nuggets on Wednesday night after missing nearly a year because of hip surgery. And Stevens, for one, was eager to take a look. Thomas had 8 points in 13 minutes in Denver’s 120-118 victory over the Kings.

“Right after the game, when I go home, the DVR is set,’’ Stevens said. “That’s what I’ll be doing after the game. I can’t wait to watch that game.’’

Thomas has been sidelined since undergoing surgery last March.

He was traded from the Celtics to the Cavaliers in August 2017 in the deal that brought Irving to Boston.

But he played in a total of just 32 games before being shut down. Initially, it was announced that he would be out for about three months, but then his recovery took almost an entire year.

Acting out

With 3 minutes, 36 seconds left in Wednesday’s game and the Celtics leading the Pistons, 108-92, Horford collided with Detroit’s Blake Griffin while going after a steal.

A foul was called on Horford, and after a review it was upgraded to a flagrant foul.

But when Horford was asked about it after the game, he smiled.

“Man, that was . . . Blake is a great actor,’’ Horford said. “He’s a great actor. I was going for the ball, and he sold it well. So, yeah. I don’t think that was a flagrant foul.’’