Watch: Robert Williams receives standing ovation from Celtics' fans in season debut

Williams didn't wait long to make an impact, slamming home an alley-oop from Marcus Smart only a minute and a half into his 2022-2023 season. 

The fifth-year pro underwent arthroscopic surgery on his left knee in September. Williams needed surgery on the same knee in March to repair a torn meniscus, but he returned in time for the postseason. 

The addition of Williams should give a significant boost to the Celtics, who entered play on Friday night with a game-and-a-half lead over the Milwaukee Bucks for the top spot in the Eastern Conference.

Last season, Williams averaged career highs in points (10), rebounds (9.6), blocks (2.2), assists (2.0), field goal percentage (.736), and free throw percentage (.722). 

Malcolm Brogdon told reporters on Friday that he noticed how hard Williams has worked to get back on the court and believes he'll make a "huge impact" for the Celtics. 

"He's still a young guy who takes his work serious, takes the game serious," Brogdon said. "He knows how good this team is without him, and he knows how good this team will be with him. He's been diligent in this process, and I applaud him for that."