Boston Celtics center Robert Williams III, who underwent surgery Wednesday morning to repair a torn meniscus in his left knee, is expected to be out of action for four to six weeks.

Williams could therefore return to the second round of the playoffs, according to ESPN.

The Celtics are currently third in the Eastern Conference standings with six games left before the end of regular season.

Williams has played a key role in the success of the league and the Celtics in the last two months. Williams alone kept their opponents below 40% for their shooting efficiency.

Williams – who signed a four-year $ 52 million contract extension last season – is averaging 10 points, 9.6 rebounds and 2.2 blocks per game this season.