What should I do?

[Jason Pohl]

Reraise. You've certainly got odds to put him all-in; but you don't want the big blind in the hand obviously.

J9 vs AA wins 16.46%
J9 vs AKs wins 33.46%
J9 vs A8o wins 42.29%
J9 vs 55 wins 48.30%
J9 vs T8 wins 63.64%

Opponent is likely no more than a 2:1 favorite, probably less. You're laying 1.5 bets to win 3.5 assuming the big blind will fold. In other words, you need to average 30% winning. So you have odds.

The chance that the big blind stays in is fairly small, but you're probably in trouble if he does.

--Jason