Granger is signed for 3 more years after the current one. At that point he'll 30 years old. To think that he wouldn't be productive past that is a bit of a reach. Average players production tends to drop off at age 31 or 32. And when your average, that means your probably a 10 to 14 pt's a game type player. You drop off from that and your probably down to 6 to 8 pts a game.
However, above average players tend to go a little farther. Most don't tend to drop off until age 33 or 34, and then their 20 to 25 pts a game drops to 15 to 18 pts a game. So yes, there's a drop, but even with the drop they tend to still be better than 80% of the players in the league.
So then the question is whether Granger is average or above average? I think the answer is above average. So we can assume that he'll be a very productive player, barring injury, until age 34 or 35. But I think using age as the yardstick is wrong. The real tool for measuring a players longevity is games played. Most productive players performance tends to start dropping off dramaticly when they reach around 850 games played. Not many players make it past 1000 games. Jabbar is one of those that played way past 1000 games and age 38 averaged 23.4 PPG. John Stockton is another one who at age 40 averaged 10.8 PPG and 7.7 APG. And Steve Nash is following in his footsteps at age 35 averaging 16.5 PPG and 11.0 APG.
Michael Jordan at age 38 averaged 20.0 PPG, 6.1 RPG, and 3.8 APG. Kobe is still going strong at age 31. But Kobe is rapidly approaching that 1000 game mark. And its starting to show up in little nagging injuries. Granger has played in 402 games. Remember, he didn't come into the league until he was 22 years old. At the end of his current contract he'll have played in 697 games, not counting any playoff games there might be. And he will be 30 years old. So the question at the time, would be whether we would want to give him another contract.
If you give him another 4 year contract your looking at him playing in a total of 945 games. Odds are that his production will fall off dramaticly in the last year, and maybe last two years of that contract. So another 4 year contract would have some risk. But his current contract doesn't. If we can aquire him, then I'd do it. The least of my worries is whether Whiteside will be productive enough to play big minutes at PF. Go get Granger first. Worry about everything else later.
