Opponent is winning but tight tag 11/6 AF 1.4 over 250 hands.

Poker Stars
No Limit Holdem Ring game
Blinds: $1/$2
6 players


Stack sizes:
HERO: $200
UTG+1: $235.40
CO: $155.55
Button: $366.80
SB: $192.95
BB: $475.90

Pre-flop: (6 players) HERO is UTG with
HERO raises to $8, UTG+1 calls, CO folds, Button calls, 2 folds.

Flop: ($27, 3 players)
HERO bets $18, UTG+1 folds, Button calls.

Turn: ($63, 2 players)
HERO bets $38, Button calls.

River: ($139, 2 players)
HERO checks, Button bets $92, HERO folds.
Uncalled bets: $92 returned to Button.

Results:
Final pot: $139


I was about to push the river... but thought long and hard about it. I'm not sure what he calls with in that spot that doesn't have me beat. I may get him to fold a better hand if he thinks I have AK, but that's unlikely.

As tight as he's been playing... and the fact he bets $92 instead of pushing... does the river look like a fold to anyone else? I get the nagging feeling I'm up against a set or two pair. Do I beat anything?