I wonder if it's humanly possible for our man Z to play a tad bit longer than even 2010? It may not even be an option, but what if Z's still just as effective as 2008? What if he's still capable of putting up 14 and 9 this year? If he can do that effectively now, then he may pick up the option for next year, hoping he can win a ring in the process? Maybe he'll do 12 and 7 again? Another year to go ring-hunting? What if he's only losing a LITTLE effectiveness?
Reason I'm asking is that he has a bad problem with feet and back, but these medical exercises and machines they're using now may allow him to play comfortably enough to want to play a little longer, even if it just prolongs his career to 2 years instead of 1.
I just look back to every NBA center who continued to play beyond their prime.
In the most recent example, Dikembe is capable (at least to the best of my knowledge) of putting up halfway decent numbers into 41 and 42. He's still 3 to 4 years away from making history, but he can clearly put up 4 points and 8 rebounds if he wanted to. That is probably his best ability at this point (and he's able to happily put that up because he's just a backup at this point), since he wasn't a big stats guy to begin with (only 10 points and 14 rebounds in his prime).
In Hakeem's and Patrick's example, they were known 20-10 players that did that every single year of their careers. And way past their primes too (In '96-'98, they weren't as healthy, but still dangerous low post scoring threats at ages of 36-38). In 2001, they both had less than 8 points and 3 rebounds, which told them "Geez! That's it?! I can't do this anymore!" Those stats were appropriate comparisons to call it quits.
And what about Kareem and Rob Parish? They went into their 20th and 21st seasons, yet despite the last couple of years left in the tank were still capable in limited exposure. Rob was only good for 4 and 2, but Kareem was so damn good that he could get 10 and 5 in only 20 minutes!
I think Z's career has no chance of getting into the 36-38 years like Ewing and Olajuwon, but he can still pull for around 34. But I wish he had great luck, because those injuries will act up in a short time. Hopefully, he can still feel good to try to put up with them beyond 2010. He'll probably retire if he can't deal with it or he starts deteriorating too much (only 3-6 points and 2 rebounds...).
Now you all at least have an idea of what Z's time span is... The fact that he's taller than most means he has a better chance of being more effective longer... Despite the ruptured disc and same old feet. He just won't be as fortunate as Mutombo, maybe even Kevin Willis (who already expired despite playing 21 seasons as well)...