Kevin Garnett went up for a dunk late in the first quarter against the Pistons Wednesday night, and by the time he came down the Celtics’ season flashed before everyone’s eyes. What’s wrong with Garnett is still not entirely clear, although it appears that the Celtics, and Garnett, may have dodged a major bullet.

Garnett had X-rays in Detroit, which were negative. That ruled out a possible fracture. According to a tweet from Yahoo’s Adrian Wojnarowski, Garnett is scheduled to have an MRI back in Boston on Thursday. The Celtics initially called it a “lower leg injury,” which could mean anything.

After the game, Celtics coach Doc Rivers suggested the injury was muscle-related, likely to Garnett’s calf, and was not a knee injury. Rivers also said that it’s likely that Garnett will miss some games. They will know more after the MRI.

On their official Twitter account, the Celtics posted the following message: “Official word on KG: Muscle injury to the outside of his right leg, below the knee and above the ankle. MRI tomorrow.”

On the play, Garnett went up clean and didn’t land awkwardly, but he was obviously in pain. He hobbled up the court and had to intentionally foul Tayshaun Prince to stop the game. Garnett then crumpled to the ground and tried to stretch out his leg before being helped to the bench. Garnett was able to make his way back to the locker room under his own power, but he was clearly limping.

In 2009, Garnett was injured in a February game against Utah when he went up for an alley-oop. As in the Detroit game, there was no contact, but that doesn’t mean the two incidents are related. Garnett’s 2009 injury was a strained popliteus tendon on top of bone spurs that had been bothering him all season, and he had surgery in the offseason to remove the spurs.

Here’s the play from Wednesday: