Tim Duncan blocks Kevin Durant, effectively stopping time (VIDEO)

Age affects knees. It makes them less durable and less springy.

Tim Duncan is 36. This makes him old for an NBA player. So he works around it.

The San Antonio Spurs center's block on Oklahoma City Thunder forward Kevin Durant, 24, is proof that you don't need to jump out of the gym to swat a shot. Duncan allowed Durant to seemingly slip past him, then slapped the ball as Durant went up for a dunk.

"Tim Duncan doesn't turn back time. He freezes it. Been freezing it," Bleacher Report NBA columnist Ethan Sherwood Strauss tweeted.

See for yourself:

Duncan later added another big-deal, timeless play with a huge dunk on 23-year-old forward Serge Ibaka. It was almost as if he wanted to remind everyone that he's good at this basketball thing.

That's how it's done, Kevin.

Duncan blocked three shots against 19-year-old Anthony Davis and the young New Orleans Hornets on Wednesday night. You figure he had to ice his knees after that kind of performance. But he bounced back quickly.

Los Angeles Lakers center Dwight Howard, who still can jump out of the gym, could learn from this, after he was posterized on a similar play by Portland Trail Blazers forward Nicolas Batum.