NL50: Battle of the blinds - huge river overbet from SB

[slickss]

Just sat down at the table so I have no reads or particular image.

<font color="black">Stack Sizes</font>
SB: $51.65
Hero (BB): $43.25
UTG: $43.60
UTG+1: $15.05
MP1: $4.20
MP2: $37.85
MP3: $60.10
CO: $42.40
BTN: $82.55

<font color="black">Preflop:</font> T[img]/images/graemlins/spade.gif[/img] A[img]/images/graemlins/spade.gif[/img] ($0.75, 9 players)
UTG folds, UTG+1 folds, MP1 folds, MP2 folds, MP3 folds, CO folds, BTN folds, <font color="red">SB raises to $1</font>, <font color="red">Hero raises to $3</font>, SB calls $2

<font color="black">Flop:</font> 8[img]/images/graemlins/club.gif[/img] J[img]/images/graemlins/heart.gif[/img] Q[img]/images/graemlins/heart.gif[/img] ($6, 2 players)
SB checks, Hero checks

<font color="black">Turn:</font> 8[img]/images/graemlins/club.gif[/img] J[img]/images/graemlins/heart.gif[/img] Q[img]/images/graemlins/heart.gif[/img] [K[img]/images/graemlins/heart.gif[/img]] ($6, 2 players)
SB checks, <font color="red">Hero bets $3</font>, SB calls $3

<font color="black">River:</font> 8[img]/images/graemlins/club.gif[/img] J[img]/images/graemlins/heart.gif[/img] Q[img]/images/graemlins/heart.gif[/img] K[img]/images/graemlins/heart.gif[/img] [5[img]/images/graemlins/diamond.gif[/img]] ($12, 2 players)
<font color="red">SB bets all in for $45.90</font>, Hero ?

Can I call this? Wouldn't he bet less on a potential flush to make sure he gets value for it?