We are deep into a tourney with 13 players left (9 player final table). Villain has been fairly aggressive throughout our time in the tournament and is 28/17 over 93 hands. We have seen villain call from SB with pocket pairs and some Ax (seen at showdown) and possibly other hands (did not make it to showdown). No other reads.

UTG: 72.39 BB
MP: 33.60 BB
CO: 15.20 BB
Hero (BTN): 35.85 BB
SB (Villain): 40.76 BB
BB: 21.73 BB

6 players post ante of 0.13 BB, SB posts SB 0.5 BB, BB posts BB 1 BB

Pre Flop: (pot: 2.25 BB) Hero has A 9

fold, fold, fold, Hero raises 2 BB, SB calls 1.5BB, fold

Flop: (5.75 BB, 2 players) 9 J 7
SB checks, Hero: checks

Turn: (5.75 BB, 2 players) 9 J 7 7
SB bets 2.5 BB, Hero calls 2.5 BB

River: (10.75 BB, 2 players) 9 J 7 7 J
SB bets 10.75 BB, Hero ???

I feel like he could be trying to get me to fold A high here to avoid a possible chop, so having a 9 means I beat those bluffs. Thoughts?

Im not folding. Too much Ahi or worse in our range on the river. Not blocking clubs or straight draws is good too.

I agree, villain has a lot of worse hands there.