Celtics center Robert Williams underwent an arthroscopic procedure on his left knee this week. On Tuesday, ESPN’s Adrian Wojnarowski reported the procedure would be happening, calling it a ‘clean up’ and  relaying that the 24-year-old was expected to miss four to six weeks.

The Celtics confirmed the procedure on Twitter on Friday, but the timeline for Williams’ return appears to have changed. Now, Williams is “expected to return to basketball activities in 8-12 weeks.”

Based on the previous timeline, Williams would have missed only a few of regular season games. Now, the earliest he is projected to return is late November, with the longer end of that window running to the week before Christmas. That’s also his timeline to ‘return to basketball activities’ – it’s not clear how long of a ramp up he would need between returning to the floor and returning to game action.

Williams’ knee issues trace back to a torn meniscus he suffered last season. Williams was able to return for the playoffs, but his minutes were managed including maintenance days in the postseason.

When he was on the floor, Williams was incredibly effective last season. In his first season as a full-time starter, he averaged 30 minutes per game in 61 games (all starts). He averaged 10 points, 9.6 rebounds and 2.2 blocks per game and worked his way into the Defensive Player of the Year conversation before his injury pulled him off the floor for the final two months of the regular season. The Celtics were 40-21 when Williams played, and 11-10 when he didn’t.

With Williams out, the Celtics will need to turn to their frontcourt depth early in the year. They’ve signed a number of potential centers to training camp and/or ‘prove it’ deals this summer including Bruno Caboclo, Noah Vonleh, and Mifondu Kabengele. They also have the 7-foot-2 Luke Kornet, who returns after spending the second half of the season with the Celtics last year in a reserve role.

The Celtics are set to begin training camp on Tuesday. Their preseason schedule begins on October 2.

Alex Barth is a writer and digital producer for 985TheSportsHub.com. Any opinions expressed do not necessarily reflect those of 98.5 The Sports Hub, Beasley Media Group, or any subsidiaries. Thoughts? Comments? Questions? Looking for a podcast guest? Let him know on Twitter @RealAlexBarth or via email at [email protected].