Tim Duncan spent 19 seasons with the San Antonio Spurs and it felt like he was never going to retire, but the five-time NBA champion decided to call it a career after the 2015-16 season.

Just like he did throughout his career, Duncan has been flying under the radar since he retired from the NBA and he has apparently found a new hobby to occupy his time.
 

 

I'm very blessed to train with the best . #timduncan #goat #EcholsFitness #kickboxing #martialartstraining #spurs #nba

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The 15-time NBA All-Star has been training with Jason Echols, a professional martial arts instructor and trainer and a Hooft Kickboxing System affiliate, and it turns out he’s a pretty good kickboxer.
 

In a recent interview with Bleacher Report’s Joon Lee, Echols had nothing but good things to say about Duncan and his kickboxing skills.

“His ability to want to learn and continue learning. We play a little game called violent chess. His intensity and strategical thinking—being in front of someone like that is extremely intimidating because of his size. I think most of all, his athleticism and size has surprised me the most. He's a roaring lion, and I can see his passion—he has to turn it down a bit. If I hold up the mitts, he could just let it go and tear my arm off,” said Echols when asked about what surprised him most about working with Duncan.

He didn’t stop there, though. Echols also thinks that Duncan would be able to hold his own in an actual fight, but doesn’t encourage him to give it a try considering he’s a retired basketball player and not someone who has spent their entire life training for the sport.

“He's my No. 1 student by far. Again, his athleticism and size and competitive spirit and his exposure to being an athlete. I jokingly said to someone else that it could be a cupcake-baking contest and he would win because he's just good at whatever he does. The sophistication level of him absorbing the martial arts that we have is very, very high. It's not hard for him to catch up with his capabilities.”
 

Echols thinks that Duncan would be able to hold his own in a fight, but wouldn’t recommend him going up against a professional considering he’s a retired basketball player and the professional fighters have been training their entire lives.
 

(H/T Instagram/echolsfitness, Bleacher Report)