edit: i didn't see that it was rush to start with
fold pre, check-fold flop, block-fold river $2
as played river needs more reads than you got. Like, he thinks A6 is the nuts here sometimes, he bluffs Qc7c here sometimes, he has A4 sometimes - this is a tough decision that even small pieces of information make infinitely easier. It probably doesn't matter much whether you call or fold, i think fold cos he's gone to some effort with his betsizing rather than simply mashing the bet-pot button.