DALLAS -- Dirk Nowitzki has been ruled out of the Mavericks' season opener and is expected to miss several games as he continues to rehab from April ankle surgery.

"It's going to be multiple weeks, I can tell you that," Mavericks coach Rick Carlisle said Friday. "But there's no real soft or hard date [for Nowitzki's return] at this point. He is doing better but has not done any significant court work. His rehab work is ongoing, and we can update you in another 10 days or something like that."

Forward Harrison Barnes' status for Wednesday's season opener against the Phoenix Suns is questionable due to a hamstring strain that has sidelined the Mavs' leading scorer for the entire preseason.

"He's doing better each day," Carlisle said. "His availability for the first game is going to hinge on whether he can get any quality practice time in between now and then."

Nowitzki, 40, has not practiced in training camp or the preseason. He suffered a setback while playing pickup ball the week before camp opened, experiencing significant soreness in the tendon in his left foot and ankle.

The operation in April removed bone spurs from that ankle.

The sixth-leading scorer in NBA history, Nowitzki has been remarkably durable for most of his career, but he has missed extended stretches in two of the past six seasons due to injuries. He missed the first 27 games of 2012-13 after undergoing arthroscopic knee surgery during the preseason, and he was out for 24 of the Mavs' first 29 games in 2016-17 due to Achilles soreness.

Nowitzki averaged 12.0 points and 5.7 rebounds in 77 games last season; he also averaged 24.7 minutes per game, the fewest since his rookie season. His minutes will likely decrease more this season, as the Mavs plan to bring Nowitzki off the bench.