(Photo by Ronald Martinez/Getty Images)

Reports are coming in that Tony Parker will remain with the San Antonio Spurs beyond the 2014-15 season.

Parker ranked 21st in win shares (5.9) among guards playing at least 60 games last season and was instrumental in the Spurs most recent championship run. But is three years, $45 million too much and/or too long?

As expected, the older an NBA guard gets, the less impact he will have on the game. The chart below shows all NBA guards and their average win shares per 48 minutes as a group. As you can see, there is a steady, but not abrupt, decline from ages 33 to 36 and then things start to really go downhill from there.


Perhaps not surprisingly, the new extension covers Parker’s seasons form ages 33 to 35 – right before the decline. So the term is right, but what about the cost?

In today’s NBA, teams pay $1.65 million per win, so some quick back of the envelop math tells us that Parker’s 2013-14 campaign (5.9 win shares) was worth approximately $9.7 million – far short of the reported $15 million per year extension. If we try and project Parker’s contributions for next year, we can come up with a conservative 7.2 win shares. Not as much as 2012-13, but not as low as 2013-14 either. That would be worth $12 million, which is right in line with the $12.5 million due to him for the upcoming season. Parker would need nine win shares or more to justify an on-court value of $15 million.

Here is the list of guards who have turned in a nine win share or greater season at 33 years or older in the history of the NBA: John Stockton (four times), Reggie Miller (twice), Ray Allen, Kobe Bryant and Steve Nash.

Allen will likely join LeBron James in Cleveland and made $3.2 million last season. Kobe will make more than $23 million in each of the next two years, but you can argue his off-court value fuels a good portion of that. Nash, in what could be his last season, will make $9.7 million.

Could Parker be as valuable as those three in the upcoming years? Perhaps, but history says to bet against it.