100r low pair river spot

[djk123]

villain is legrouzin.. don't really know who he is.I can't see him making a thin value bet here, so it's gotta be monster or a missed draw i think. what would you do?
Poker Stars
No Limit Holdem Tournament
Blinds: t100/t200
9 players
Converter (http://www.neildewhurst.com/hand-converter)

Stack sizes:
UTG: t11935
UTG+1: t14425
MP1: t7432
MP2: t11156
djk123: t14430
CO: t14158
Button: t4125
SB: t10978
BB: t17991

Pre-flop: (9 players) djk123 is MP3 with 4/images/graemlins/diamond.gif 4/images/graemlins/spade.gif
UTG folds, <font color="#cc0000">UTG+1 raises to t600</font>, 2 folds, djk123 calls t600 <font color="aaaaaa">(pot was t900)</font>, CO calls t600 <font color="aaaaaa">(pot was t1500)</font>, 3 folds.

Flop: 6/images/graemlins/diamond.gif 9/images/graemlins/club.gif 3/images/graemlins/diamond.gif (t2100, 3 players)
UTG+1 checks, djk123 checks, CO checks.

Turn: 6/images/graemlins/heart.gif (t2100, 3 players)
UTG+1 checks, <font color="#cc0000">djk123 bets t1400</font>, CO calls t1400 <font color="aaaaaa">(pot was t3500)</font>, UTG+1 folds.

River: 2/images/graemlins/spade.gif (t4900, 2 players)
djk123 checks, <font color="#cc0000">CO bets t3800</font>, djk123

[curtains]

probably I'd fold.