Where are the Duncan Defenders who were saying that Duncan can play 35+minutes a game? He's averaged nearly that many this season and now he is continually banged up and is missing games. If it's not an ankle, it's his hip or his back.
Tim is an awesome player, but he should never average more than 30 minutes per game. If you play him any more than that, he can't last many more NBA seasons and his career is going to be shortened.
Best case scenario is bringing him off the bench for something like 28 minutes a night. That way he can play an entire NBA season and it will ensure that he'll still be able to walk by the time his contract is over. At this rate, he's seriously setting himself up for trouble.
When he comes back, Pop must limit his minutes. From now to the end of the season, Tim has to rest up. If he doesn't, he's not going to be good enough in the playoffs for the Spurs to do anything.
This offseason, I'd really consider making it known that Tim is going to be the first big man off the bench and going out and finding a starting power forward. Tim's not going to make it at this rate.