[HighStakesPro]

You have to call (and show if you lose) here with 9.333 to 1 pot odds and hope he has a smaller pocket pair, overcards with one diamond (admittedly not likely), or something like J9. But just as importantly, you get to look him up and see whether he was capping with a big hand like overpair/trips, top pair, or a straight/flush draw, especially since you just got to the table. Plus, I've found that it is generally a bad idea to have a "fold-on-the-river" image, it's generally more profitable to have people call you down on your legitimate hands then to call them down and hope they're bluffing. If they know you'll call them down with a legitimate hand, the observant ones won't try to bluff you on the river as much, allowing you to check behind them, or fold if they bet, knowing that it's likely they have a real hand.