NL50: AJs 3bet OOP vs very laggy player

[Maunzekater]

Full Tilt Poker, $0.25/$0.50 NL Hold'em Cash Game, 6 Players
LegoPoker Hand History Converter

BB: $51.25
UTG: $50
MP: $103.10
CO: $40
BTN: $203.75
Hero (SB): $85.50

Pre-Flop: A[img]/images/graemlins/diamond.gif[/img] J[img]/images/graemlins/diamond.gif[/img] A[img]/images/graemlins/diamond.gif[/img] J[img]/images/graemlins/diamond.gif[/img] dealt to Hero (SB)
3 folds, <font color="red">BTN raises to $1.75</font>, <font color="red">Hero raises to $5.75</font>, BB folds, BTN calls $4

Flop: ($12) 7[img]/images/graemlins/heart.gif[/img] Q[img]/images/graemlins/diamond.gif[/img] Q[img]/images/graemlins/club.gif[/img] (2 Players)
<font color="red">Hero bets $8</font>, BTN calls $8

Turn: ($28) A[img]/images/graemlins/heart.gif[/img] (2 Players)
Hero checks, <font color="red">BTN bets $5</font>, Hero calls $5

River: ($38) 4[img]/images/graemlins/diamond.gif[/img] (2 Players)
Hero checks, <font color="red">BTN bets $6.75</font>, Hero calls $6.75

Villian's stats are 48/26/3.2/110, all hands from this session. ATS 57%(16/28)! I don't know how his stack became so big, this is the first bigger than average pot he is involved in. He folded a lot when facing resistance postflop.

He could very easily have a Q here, that's why i switched to check-call mode after he called my c-bet (to be honest, i was quite lost in this hand).