It's been a dominant tournament for Rafael Nadal, and the quarter-finals were no different.

The defending champion dismantled American Andy Roddick 6-2 6-1 6-3 in under two hours. It was another overwhelming performance by Nadal, and another setback for Roddick.

Nadal had 22 forehand winners in the match, while Roddick failed to get even one, and only had one backhand winner. The Spaniard has yet to drop a set in the tournament.

Overall, it was a disappointing effort for Roddick, who has been battling a leg injury and received two leg rubdowns from a trainer during the match. His leg was certainly giving him problems on his serve.

It's a bad feeling. It's almost worse than competing, Roddick said after the match. You feel helpless.

Nadal will face fourth-ranked Andy Murray in the semi-finals on Saturday.

It will be a very tough match for me, Nadal said, and hopefully for him, too.

First Lady Michelle Obama was on hand and sat next to Billie Jean King.

Take a look at the highlights of Nadal - Roddick.