The Boston Celtics didn't add frontcourt depth prior to the 2020 NBA trade deadline -- in part because they're expecting an internal addition.

Celtics big man Robert Williams hasn't played since Dec. 6 due to a left hip injury. But in an interview Friday on 98.5 The Sports Hub's "Toucher & Rich," Celtics president of basketball operations Danny Ainge said Williams is on track to return in a little under a month.

"Robert Williams is progressing," Ainge said. "He was out working on the court (Thursday). He's starting his transition back into all the live action, and we anticipate him being back with us somewhere in the neighborhood of March 1."

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Williams was diagnosed with a bone edema in his left hip in mid-December and was expected to miss at least three weeks. That timeline has dragged out to nearly two months, but it appears the Celtics still expect him back for their playoff push.

The 22-year-old center was averaging 3.9 points, 4.6 rebounds and 1.1 blocks through 19 games played prior to his injury.

The Celtics' frontcourt has played well in Williams' absence, but with big men Enes Kanter and Daniel Theis battling their own injuries -- Theis isn't expected to play Friday night against Atlanta due to a sprained ankle -- Williams' return will be a welcome sight.

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