Kyrie Irving underwent successful surgery on Saturday to remove two screws from his left knee, according to the Celtics.
The All-Star guard is expected to be sidelined for 4-5 months after the procedure, but the team expects a full recovery.
"The surgery went exactly as planned, and we expect Kyrie to be fully healthy for training camp in the fall," Danny Ainge said in a statement.
Al Horford reflected on the challenge that the Celtics now face without Irving on Saturday for the postseason.
"Obviously, it makes it more difficult," Horford said. "Kyrie is the leader of this team, and we went with him and now we have to find ways to do it without him. We've been playing good basketball, and I believe that this group will -- we have a group that's hungry and that wants to keep getting better. And I think that when you have a group that wants to keep getting better, it's always a positive."
The Celtics are locked into the No. 2 seed in the East but could still face up to three different teams in the first round based on how the final four days of the regular season pan out. The Bucks are currently in the No. 7 spot as of Sunday morning.