Tim Duncan kickboxer

San Antonio Spurs legend Tim Duncan retired from the NBA last summer, but he’s keeping himself busy… with MMA.

Apparently, the legendary NBA star has been heavy in the gym during his retirement, training as a kickboxer. And, his coaches say he’s good enough to compete professionally.

In an interview with Bleacher Report, Duncan’s trainer Jason Echols‏ calls him “a f*cking monster” and a “legit competitor” in MMA.

“[Duncan] would be a legit competitor. For sure,” says Echols. “He has a desire to learn and compete. He has the heart for it. He most definitely would be a competitor.”

“I would highly encourage him not to. Being a retired Spurs player, I wouldn’t want him going out there and getting punched and kicked by some of those guys, but Tim would be a competitor,” he added.

Check out the brief training clip of Duncan below and you be the judge.