Each day during the 2011 U.S. Open, coach Nick Bollettieri will discuss three of the most intriguing matches on the schedule and offer his predictions.

Roger Federer [3] vs. Marin Cilic [27] (Arthur Ashe Stadium, second match)

This is the first real test for Federer, as Cilic comes into this match playing great tennis and should be full of confidence. I said before the tournament that I liked Federer’s chances of winning this event, and he has done nothing so far to change my opinion. Cilic has beaten two of the best up-and-comers in the world in Ryan Harrison and Bernard Tomic, and both times I have picked him to lose! Well, I guess I am going to try my luck again with him!

Federer is 2-0 against Cilic, which includes a win over him earlier this year in Monte Carlo. Cilic has played some unbelievable tennis in the first two rounds and will have to play even better to knock off Federer. His groundstrokes are excellent, he has a sonic serve and for a big boy he moves really well. He thrives off of his opponents’ pace, and that is where I think Federer can make an impact. Federer has the ability to change the pace and play with more variety than Harrison or Tomic did. He also has the big serve to get out of tough positions and he isn’t making very many mistakes right now. I think Cilic can win a set and keep it interesting, but I have to pick Federer to advance.

Nick’s Pick: Federer in four sets

*

Victora Azarenka [4] vs. Serena Williams [28] (Arthur Ashe Stadium, third match)

Serena cruised to an easy win over Michaella Krajicek in the second round, but I don’t think she is going to have such a good time against Azarenka. When you seed Serena this low, this is the kind of match you are going to get in the third round, which is unfortunate for both girls.

Serena is 5-1 against Azarenka and beat her recently in the semis of Toronto, in straight sets. If you are heading out to watch this match, you better bring your helmet and shield because each girl is going to be firing missiles! Both girls are going to play extremely aggressive tennis and neither is going to back down from the challenge. I know Serena hasn’t played much tennis this year, but every time she takes the court I think she is going to win. If she falls behind early, Azarenka won’t waste any time jumping all over her, but in the end, I have to give the edge to Serena.

Nick’s Pick: Williams in three sets

*

Novak Djokovic [1] vs. Nikolay Davydenko (Arthur Ashe Stadium, second night match)

Djokovic almost pulled off the rare feat of triple-bageling an opponent in the second round, beating Carlos Berlocq, 6-0, 6-0, 6-2. What can I say about Djokovic that hasn’t been said before? The man is playing some of the best tennis in the history of the game and there appears to be no end in sight!

Djokovic is 4-2 against Davyenko and the two just met in Canada, where Djokovic won, 7-5, 6-1. A few years ago this match would have been a quarterfinal or semifinal, but that isn’t the case anymore. I watched Davydenko’s whole match against Potito Starace in the second round and he still moves well, has solid groundstrokes and can get free points off his serve. Starace stood well behind the baseline, though, which gave Davydenko more time to recover before each shot. That is definitely not going to happen in this match. Djokovic loves to catch the ball early, on the rise, and keep his opponents off-balance. As I have said recently, right now, Djokovic is playing at a level that we have never seen in the sport. He has no weakness in any part of his game and he can place the ball anywhere he wants. I look for Djokovic to continue his amazing 2011 with a straight-sets victory here.

Nick’s Pick: Djokovic in three sets

Nick Bollettieri of the IMG Bollettieri Tennis Academy has trained many collegiate and professional players, including 10 who reached the world No. 1 ranking.