99s middle position

blinds 30/60, early MP player raised to 250, I coldcalled, everyone else folded. Flop was A, K, 8, rainbow. He bet 60 (minimum), I raised to 300, he folded.
The 60 felt like a feeler bet, risking the min for info. I figured a raise takes it down and I was right. If he had raised, I could have folded without losing too many chips; if he called my raise, I'd re-evaluate on the turn.