Stars 10re/ Push to isolate button + dead money

[Rickyroodido]

The button is "TheBoss", and I figured he needed chips so I thought my A8s was good. I was fairly certain that the tight SB had me beat though, but since he didnt isolate I figured he would fold to a push leaving 28k dead.
Horrible or brilliant?!

PokerStars No-Limit Hold'em Tourney, Big Blind is t4000 (9 handed) internettexasholdem.com

Button (t28353)
SB (t70351)
Hero (t90150)
UTG (t33608)
UTG+1 (t38496)
MP1 (t134863)
MP2 (t115767)
MP3 (t20591)
CO (t48528)

Preflop: Hero is BB with A[img]/images/graemlins/heart.gif[/img], 8[img]/images/graemlins/heart.gif[/img].
<font color="#666666">6 folds</font>, <font color="#CC3333">Button raises to t28153</font>, SB calls t26153, <font color="#CC3333">Hero raises to t89950</font>