[gumpzilla]

It's possible I'm being results oriented here, but it seems like this is deep enough that the idea of protecting your stack rather than your hand might be good.

If he's a standard TAG, what is he going to get a lot of money in here with? Standard TAGs are 3betting PF with QQ+, most likely, and probably being more aggressive on the flop with combination draws. They aren't super likely to be check calling two streets with AJ. So, what hands do you think you're getting value from when you bet the turn? Virtually anything that's going to think about calling if your read is good is not in his range. I guess my point is that I think you can make a strong argument for checking behind on the turn.

Anyway, your only chance, really, seems to be that he is running a rather weird bluff - I doubt he's playing J9 for value this way. That's certainly possible - particularly given your goofy flop bet - but I think it's more likely this is 99 or JJ waiting for a safe turn to pump a lot of money into the pot.