Tim Duncan is 38-years-old and is playing in the middle of his 18th NBA season. Considering the repeated postseason runs he's enjoyed in San Antonio, that's a lot of wear and tear for any player, especially one approaching 40. Several fans believe Duncan may finally hang it up after this year, though not everyone is as convinced.

"No matter how (the season) ends, I think Timmy is going to look at (retirement) again," Spurs head coach Gregg Popovich said to USA Today. "And if you ask me, my guess is that he'll go for another one because he has been so consistent this season. It's just consistent stuff: another double-double, over and over and over again. Because of that, I think in his mind that if it continues through the rest of the year, I think he'll say, 'I'm going to go another year and see what happens.'"

Duncan is averaging 14.5 points, 10.0 rebounds and 1.9 blocks per game this season. His player efficiency rating of 21.72 is higher than notable players such as Kyle Lowry, Kyrie Irving, Chris Bosh and Al Jefferson.

Popovich, meanwhile, signed an extension last summer but said he doubts he'll stay for the entire duration of the deal.

"It's a five-year contract, but the chances of staying for five years I don't think are very good," he said. At 66 and with five NBA championships under his belt, it's understandable if Pop wanted to hang it up in the near future.

Perhaps both Duncan and Popovich will return for one more season before calling it quits after their respective Hall of Fame careers.