Bet Sizing Head Scratcher

[user140525]

Check out this hand and see if you can figure out what's going on. Sal Fazzino opened to 650 from middle position, and Mani Rezaei called from the cutoff. Then the big blind squeezed to 2,500, but he didn't succeed in pushing out either opponent.

Flop: {a-Diamonds} {9-Hearts} {4-Clubs} - The big blind checked, and Fazzino bet 3,300. Rezaei made the call, and the big blind folded.

Turn: {5-Diamonds} - Fazzino checked this time, and Rezaei took over the aggression, sort of. He tossed out a T5,000 chip, but announced a bet of only 1,000. Fazzino called the 1/15th-pot bet.

River: {3-Diamonds} - Fazzino asked Rezaei how much he had behind, then bet the pot, enough to put Rezaei all in. He muttered something unpleasant and folded {A-Spades} {k-Spades} face up.