haas is a hard trainer, u only have to look at what he has achieved this year, no tennis for 18 months, hes won 2 tournaments after coming back from 2 major shoulder operations, that takes a lot of commitment. Hes managed to get his ranking up to 45, which is a big big effort, and those ranking points only include 2 grand slams and half of the masters series events. He has plenty of passion and trains hard.
however there are two major problems with his game, firstly he lets things get to him on the court. once the bad calls start going against him, u know hes in trouble. secondly, hise second serve has always been very suspect, he gets a good percentage of first serves in, in 2001 and 2002 he was in the top 5 on the tour for that, but he also serves a lot of double faults. if he can fix up these things theres no reason he cant be world number 1.
he was ranked top 20 when he was 19 and hasnt kicked on really, but hes got a second wind imo since coming back, Grand Slams are hard to win, so its silly to say hes going to win just like that, but i expect a good showing in the US in the next fortnight, a quarter finals spot isnt out of the question.
the last 2 times he played there he lost in the 4th round to the eventual champion both times, Hewitt 2001 and Sampras 2002.