[markuisis]

i think kings and aces r more likely to 4-bet pf oop than smooth call, i dont think nines play this fast but maybe and i doubt he has a six here, plus, i think this flop is being raised by a decently wide range, to me his raise could be something like 10s or jacks which dont want to give a free card to a hand like ak or aq but dont want to commit themselves at this point or even a hand like 10js which figures u miss this flop a decent perecentage of the time and that a raise like this will push u off ur air like ak or aqs. Aggro play would be to shove and not give a free card if u think hes got a fd, more conservative and IMO better play would be to call and re-assess turn cause its pretty much guaranteed that if u shove that flop ur not gonna get called by something u beat.