Robert Williams won't be returning to action anytime soon.
The Boston Celtics big man has been diagnosed with a bone edema in his left hip, the team announced Monday.
Williams will be reevualated in about three weeks and must limit basketball activities during that span, according to the Celtics.
An edema is a buildup of fluid around a bone and can occur as the result of a stress fracture or arthritis.
The 22-year-old has missed Boston's last three games due to injury, and his absence leaves a thin Celtics frontcourt consisting of Enes Kanter, Daniel Theis, Grant Williams and Vincent Poirier.
Rookie Tacko Fall has played in just one game at the NBA level this season but could see more time with Williams sidelined.
Williams is averaging 3.9 points, 4.6 rebounds and 1.1 blocks in 14.2 minutes per game off the bench for the C's.
With players officially eligible to be traded and the NBA's Feb. 6 trade deadline approaching, it's worth wondering whether Boston will pursue additional frontcourt depth with Williams expected to miss extended time.
Don't miss NBC Sports Boston's coverage of Celtics-Mavericks, which tips off Wednesday at 8:30 p.m. with Celtics Pregame Live, and then Kyle Draper, Brian Scalabrine and Kendrick Perkins have the call at 9:30 p.m. You can also stream the game on the MyTeams App.