Raise this river?

No really strong read on UTG. He limped a fair bit - didn't seem like a very strong player but made some $ by winning a hand where he had flopped a monster - and then lost it when he couldn't let go of AA.

PokerStars No-Limit Hold'em, $0.50 BB (7 handed) FTR converter on zerodivide.cx

SB ($54.30)
BB ($86.95)
UTG ($55.25)
MP1 ($47.50)
MP2 ($18.50)
Hero ($46.45)
Button ($33.70)

Preflop: Hero is CO with 6:heart:, 7:spade:.
UTG calls $0.50, 1 fold, MP2 calls $0.50, Hero calls $0.50, Button calls $0.50, 1 fold, BB checks.

Flop: ($2.75) 8:spade:, 2:club:, 5:diamond: (5 players)
BB checks, UTG bets $1, MP2 folds, Hero raises to $3, Button folds, BB folds, UTG calls $2.

Turn: ($8.75) Q:club: (2 players)
UTG checks, Hero checks.

River: ($8.75) 9:club: (2 players)
UTG bets $13.5

Now I successfully ran the "free card" trick - but should this river be raised, given the strength of the bet and the 3-flush bd (granted it was runner runner but still...)

To me that river bet screams "how dare you check behind on the turn after raising? I was going to check raise your ass! Now I need to bet more to make up for lost profits"

I'd raise for sure.

I like the good ol' let the timer run down and puuuuuuuush.

If he open limped 2 clubs UTG then called your flop raise (which u should raise harder imo, but it got one of your two desired effects anyway), well then, that just sucks.

I think a push gets called by a set here often enough....

I would raise also..

I think he would have come out firing on the turn had he picked up that flush draw also.

I put him on an over-pair anyways, or a complete bluff..