Ben Simmons injured his back during Saturday's loss to the Milwaukee Bucks, and he hasn't returned to the floor for the Philadelphia 76ers since. Now we know why. The All-Star point guard has a nerve impingement in his lower back, according to Shams Charania of The Athletic. He will be re-evaluated in two weeks. The prognosis is not quite that positive, however, The 76ers do not expect Simmons to be ready to play in that timeframe, according to ESPN's Adrian Wojnarowski. 

When Simmons initially got hurt, the injury was described merely as lower back tightness. Upon further evaluation, however, the impingement was diagnosed. Simmons played less than five minutes in the contest against the Bucks before exiting, never to return. He was in visible discomfort after he drove to the basket early on in the contest. Simmons also missed the Sixers' previous game against the Brooklyn Nets on Thursday night due to back soreness and was initially listed as questionable for Saturday. 

Prior to the Sixers' matchup with the Cavaliers on Wednesday, coach Brett Brown declined to give an update on Simmons' timeline. "I'm gonna stay away from all that," Brown said. "As always, I'll let the club lead the charge (when it comes to updates)."

Injuries haven't been much of an issue for Simmons over the course of his career to this point, as he missed only four total games during his first two seasons. The Sixers clearly hope the back issue isn't a serious one as they're in the midst of a tight battle for playoff positioning in the Eastern Conference. As their main offensive initiator, Simmons is central to what they do on that end of the floor, and he has also been playing elite defense all season. In short, the Sixers can't afford to be without him for long. 

On the season, Simmons is averaging 16.9 points, 7.9 rebounds 8.3 assists, and a league-leading 2.2 steals per game. He's third on the Sixers in points per game, second in rebounds, and first in assists. 

Any extended absence for Simmons could be extremely problematic for a Sixers team fighting for playoff seeding. Philadelphia is slated for the No. 5 seed in the Eastern Conference at the moment, which would not only force them to travel to Miami for the first two games of a first-round series against the Heat, but would also set them up to play against the top-seeded Bucks in the second round rather than the Eastern Conference Finals as most expected. The Sixers currently trail the No. 3 seeded Boston Celtics by four games with only 24 left on their schedule, so jumping out of Milwaukee's bracket was already unlikely. Now, this injury only makes it more so. 

With that in mind, and the flailing Indiana Pacers still 2.5 games behind them, the Sixers will likely be cautious with Simmons in his recovery. They have little to gain by rushing him back, but will absolutely need him if they hope to make a deep playoff run this spring.