Dirk Nowitzki's 21st season in the NBA has not gone as planned, but the Dallas Mavericks veteran hopes to return in December.

The 40-year-old has yet to step out on the court in his Dallas uniform after undergoing ankle surgery seven months ago.

But, not all hope is lost, because Nowitzki is setting his sights on a new goal – a December return.

"It's just hard when I haven't done much for eight weeks and there's a 40-year-old basically starting from scratch to try to get back in shape to play NBA minutes," Nowitzki said, via ESPN. "Hopefully soon. Hopefully, somewhere in December I'll be ready and the body will respond the right way."

Nowitzki had surgery to remove bone spurs from his left ankle just before the end of the 2017-18 season. The 13-time All-Star was on schedule to be ready for the start of this campaign before suffering a major setback. He was experiencing tendon soreness before the start of training camp in September, and since then had to push his timeline back.

It is a disappointing start to Nowitzki's record season with the same franchise. But, when he does return he will become the first player to spend all 21 seasons with the same team – until he makes his official debut, he technically shares the record of 20 seasons with Kobe Bryant, who retired from the Los Angeles Lakers in 2016.

"I've been antsy," he said. "I had the surgery in April and it's been nothing but rehab and treadmills. Love to step out there soon and get the kick of competing, the crowd involved. It's just something I miss. And once my career is over, that's for sure something I'll miss, the kick, the rush, the adrenaline."

Nowitzki started running on a treadmill about two weeks ago, ESPN reported, and has been increasing the intensity of his workouts ever since. He has even played in a couple of games involving Mavericks' staff members during the team's practice, but has yet to go through one full session.

"The reason why we're taking it so slow now is once I get out there, I want to finish the rest of the season healthy," Nowitzki said. "I don't want to come back too soon now and then have setbacks again like I did with the Achilles a few years ago. Next thing you know I missed another few weeks."