Opp was a good regular whose play I usually respect. This had me puzzled. Do I have to go to the races here?

PokerRoom No-Limit Hold'em, $0.50 BB (5 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

SB ($29.50)
BB ($11.60)
UTG ($20.40)
MP ($35.65)
Hero ($29.75)

Preflop: Hero is Button with A, 7.
UTG calls $0.25, 1 fold, Hero raises to $1.25, SB calls $1.10, 1 fold, UTG calls $1.

Flop: ($4) 5, A, 3 (3 players)
SB checks, UTG checks, Hero bets $3, SB calls $3, UTG folds.

Turn: ($10) 9 (2 players)
SB checks, Hero bets $5, SB bets $25.25 (All-In), Hero ??????