The Boston Celtics will host Giannis Antetokounmpo and the defending champions Milwaukee on Sunday in what is going to be the most important game of their season. It's a do-or-die Game 7 matchup with everything on the line. The winner moves on to the Eastern Conference Finals, while the loser will be sent packing on an early summer vacation.

The Celtics have provided a critical update on the injury status of starting center Robert Williams III ahead of the highly anticipated final game of the series and, unfortunately, things aren't looking too good for the 6-foot-9 big man. According to NBA insider Marc Stein, the Celtics have tagged Williams as questionable for Sunday:

Celtics say Robert Williams is questionable for Sunday’s Game 7 against visiting Milwaukee.

Williams is still dealing with a lingering knee injury that has cost him the last three games of the Bucks series. The Celtics center played through the injury in Games 1 through 3, but at this point, it sounds like he could be in real danger of missing out on Sunday's contest.

This could be Boston's final game of the season, though, so you can be sure that Williams and the Celtics will do everything they can to get him ready for Game 7.