Milwaukee Bucks center Brook Lopez hasn't played since the first game of the 2021-22 season, and he won't be playing anytime soon. That's because Lopez just underwent back surgery.

The Bucks announced that Lopez went under the knife on Thursday in Los Angeles. The big man “will continue to be listed as out and updates on his rehabilitation progress will be provided as appropriate.”

While Milwaukee is currently on a roll as winners of eight games in a row now that the star trio of Giannis Antetokounmpo, Khris Middleton and Jrue Holiday is healthy, it's still a bummer that Lopez is dealing with this issue and will miss a lot more time. Lopez has been a key contributor as a rim protector and floor spacer for the Bucks in recent seasons.

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With Lopez out, Milwaukee has been starting Bobby Portis at center. Portis is having a stellar season, averaging 15.1 points and 8.3 rebounds while shooting 48.3% from the field and 42.7% from 3-point range in 27.8 minutes per game. DeMarcus Cousins was also just signed for depth at the position.

After a sluggish start to the season, the Bucks are hitting their stride and are tied for the second-best record in the Eastern Conference. Even without Lopez for the foreseeable future, it wouldn't be a surprise if Milwaukee is on top of the conference very soon. Giannis is playing at an MVP level once again and is now getting the help he needs from his teammates.

Even so, the Bucks are hoping Lopez will be back at some point this season as they try to defend their title.