The villain seemd like a solid player, though my PT stats showed his VPIP was 34% for the few hundred hands I had him tracked for. He won at showdown 65% of the time. Would you call this, or bet it differently?

Party Poker No-Limit Hold'em, $2 BB (10 handed)

Button ($327.23)
SB ($196.12)
BB ($13.5)
UTG ($148.5)
UTG+1 ($170.02)
Hero ($631.05)
MP1 ($174)
MP2 =(Villain)/ ($155.95)
MP3 ($102.6)
CO ($223.4)

Preflop: Hero is UTG+2 with , . SB posts a blind of $1.
2 folds, Hero calls $2, 1 fold, MP2 =(Villain)/ calls $2, 2 folds, Button calls $2, SB (poster) completes, BB checks.

Flop: ($10) , , (5 players)
SB checks, BB checks, Hero bets $9, Villain calls $9, Button folds, SB folds, BB folds.

Turn: ($28) (2 players)
Hero checks, Villain checks.

River: ($28) (2 players)
Hero bets $20, Villain raises to $55

Final Pot: $138

First, I'm curious why you were playing A4s in early position. I really don't see how that hand is profitable out of position. You have 3 buy-ins so maybe you have the table fearing you and are playing very loose. What strategy did you have to get a large stack? Play this loose?

Second, I very rarely draw to the lower side of the straight, and I don't like to draw on a paired board. Two bad things on that board. Given this, I don't really see the purpose of the river bet. You will on ly get called/raised by someone who beats you on that board.
Your hand isn't concealed at all.

I would fold. You're betting almost pot size and he's raising you. I think you know you are beat. The only raising hands you would beat are trips and 2 pairs, but he has to be a moron to raise with those.

There's a reason they call it the idiot end of a straight... I think the times that I've called these, I've probably lost 80% or more... I would definitely fold...

BTW... I agree w/ Poker, and probably wouldn't have played A4 in EP, suited or otherwise...

Actually, I was playing a little loose (25% VP$IP) for the session, but very aggressive pre and post flop. While [4d] is marginal at best, a few at the table were pretty loose and I was dominating with aggressive play at that moment. You're right, I don't normally play unless I'm in late to middle position. After he called the pot-sized bet on the flop, I put him either on a high pocket pair or set, which would be good action for this weak low-end straight. After the turn paired the board, I was expecting to check/fold but then he checked instead which was either real or bluffed weakness. I think I trapped myself with the the 8 on the river, and made a bad $35 call. He turnd over 88, which I really didn't expect even though it made sense after I thought about it later. Although I've gotten a lot better at laying down vs bad calls, I still am prone to this expensive leak. Thanks for the feedback.