Perhaps this will only be of interest to Gothamist, but according to today's ESPN Insider (subscription required) a small loophole in the NBA salary cap rules might make a deal for Erick Dampier unlikely.

The Knicks are currently offering Dampier a six-year, $71 million deal with a starting salary of $9 million plus yearly 12.5 percent raises. However, Dampier's agent Donald Fegan wants the Knicks to add a seventh year to the deal, which they would be able to do if the Warriors agree to this via a sign and trade deal.

Erick DampierThis is where the catch comes in. Dampier is already 30 years old. If the Knicks add that seventh year (which they would have to do to outbid other teams under the salary cap), then the little used "over 36" rule would be in effect. It basically say that when a team signs someone to a long term contract , it is very unlikely that the player in question will actually be playing when he is over 36 (he's more likely to be retired or permanently on IR). Therefore the league automatically pro-rates the pay that would be due to the player when he turns 37 over the length of the contract that occurs when the player is 36 or younger.

So in this case, the last year of Dampier's proposed contract (should the Knicks give him the seventh year his agent wants), that being $16.38 million, would be pro-rated over the first six years of his contract. An extra $2.73 million would be added to his salary for the first six years of the contract for salary cap purposes. So instead of having a $9 million cap hit for Dampier in year one, it would instead be almost $12 million.

Under those circumstances, the current package the Knicks are offering for Dampier wouldn't cut it. They'd have to add more salary.

That concludes today's lesson on NBA salary cap economics.