River decision with ATo

[gharp]

Dramatis Personae:

BB in this hand is super-passive: 50/0/0.1 over 100+ hands. I have literally never seen him raise. He just calls down flushes, sets, etc -- he varies from your garden variety loose-passive in that he sort of knows how to fold post-f, but calls down with anything remotely reasonable.

UTG is his loose bizarro twin: 59/26/2.1 (100+ hands) Very LAGgy and very bluffy. I've seen him cap the turn w/garbage, bet into pf raisers on scary boards with bottom pair, etc.



Act I:

Ultimate Bet 3/6 Hold'em (6 handed) FTR converter on zerodivide.cx

Preflop: Hero is SB with T[img]/images/graemlins/spade.gif[/img], A[img]/images/graemlins/diamond.gif[/img].
UTG calls, <font color="#666666">3 folds</font>, <font color="#CC3333">Hero raises</font>, BB calls, UTG calls.

Flop: (6 SB) 8[img]/images/graemlins/heart.gif[/img], Q[img]/images/graemlins/heart.gif[/img], 9[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(3 players)</font>
<font color="#CC3333">Hero bets</font>, BB calls, UTG calls.

Turn: (4.50 BB) 3[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(3 players)</font>
Hero checks, BB checks, UTG checks.

River: (4.50 BB) 9[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(3 players)</font>
Hero checks, BB checks, <font color="#CC3333">UTG bets</font>, Hero...?


Is this an easy decision? Comments on any and all streets appreciated...