Brooklyn Nets forward Ben Simmons has been out since last month with a knee injury, but he now has an additional issue with his back.

"During his strengthening process he did experience some back soreness," coach Jacque Vaughn told reporters Friday. "So now we're in the process of strengthening the knee while also managing the back."

Simmons hasn't played since Feb. 15 before the All-Star break. The guard dealt with a back injury throughout the 2021-22 season, requiring offseason surgery, but Vaughn was unsure if the latest issue is in the same area, via Brian Lewis of the New York Post.

The 26-year-old is averaging 6.9 points, 6.3 rebounds and 6.1 assists in 42 games (33 starts) for the Nets. He's shooting 56.6 percent from the field and averaging 26.3 minutes per game.

Simmons missed his team's Feb. 24 matchup against the Chicago Bulls with left knee soreness. Head coach Jacque Vaughn spoke about the player's status pregame and noted he was set to miss the Feb. 26 game against the Atlanta Hawks as well:

Simmons spoke with reporters about his rehab and frustrations with his knee, which has kept him sidelined at numerous times this year:

"I had it drained right before All-Star. I also had a PRP. It's frustrating, but it's something that's an injury I've never dealt with before. So it's something I'm learning about, that we're learning about.

"I didn't have a normal All-Star [break]. I was rehabbing the whole time still, after the PRP. So my break was just rehabbing and it was trying to get back out there. And then obviously, we played five-on-5-five three days ago, four days ago, which was good. But [I] wasn't moving, I didn't move and didn't have that strength."

It's been a frustrating season for Simmons, who hasn't been able to showcase the form that made him a three-time All-Star in Philadelphia. Adding another injury only makes it more difficult for him to stay on the court unencumbered.

There is no timetable for a return, although there has been no discussion of shutting down for the season, as Vaughn explained Friday.