interesting river spot vs roothlus in stars 50r

[flopmonster]

2nd hour. roothlus had been playin a lot of pots so far. i don't really put him on a 9 since he checked behind the turn but I can't imagine he would call a shove on the river with a q so i see no point in raising in case of the small chance he has a 9. thoughts?

PokerStars No-Limit Hold'em Tourney, Big Blind is t200 (8 handed) internettexasholdem.com

SB (t4295)
BB (t2950)
Hero (t24585)
UTG+1 (t5975)
MP1 (t5525)
MP2 (t16760)
CO (t9895)
Button (t8850)

Preflop: Hero is UTG with Q[img]/images/graemlins/heart.gif[/img], Q[img]/images/graemlins/club.gif[/img].
<font color="#CC3333">Hero raises to t600</font>, <font color="#666666">2 folds</font>, MP2 calls t600, <font color="#666666">3 folds</font>, BB calls t400.

Flop: (t1900) 2[img]/images/graemlins/heart.gif[/img], Q[img]/images/graemlins/diamond.gif[/img], 9[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(3 players)</font>
BB checks, Hero checks, <font color="#CC3333">MP2 bets t800</font>, BB folds, Hero calls t800.

Turn: (t3500) 9[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, MP2 checks.

River: (t3500) 9[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets t2200</font>, <font color="#CC3333">MP2 raises to t4400</font>, Hero