The world's No.1 tennis player, Rafael Nadal, might have already advanced into the final of the Qatar Open, but he sure won't forget his first match with Lukas Rosol since losing to the same man in the second round of the 2012 Wimbledon Open Championship.

Nadal--who defeated Peter Gojowczyk, 4-6 6-2 6-3, to book a spot in the final round--admitted that he felt uneasy playing the last man that defeated him before taking a seven-month hiatus due to a bothersome knee injury.

Though he has no ill feelings or sense of revenge towards the Polish tennis player, Nadal admitted that his victory against Rosol wasn't easy at all. In fact, he felt his foe's playing style gave him such a hard time on the court.  

"Well, I never take revenges, first thing. Thinking about revenge is a bad way to start the match, my opinion.  You have to start with the calm and with the mind very open to analyze what's going on in the match," Nadal said during a post-game interview via Rafael Nadal Fans.

"I was a little bit nervous.  I didn't have a great memory of the last match playing against him.  After that match I didn't play not one more match in a tennis court for almost eight months, so it was a bad feeling in that moment," he added.

Nadal said Rosol's ability to hit the ball low challenged him in the match, though he also blamed himself for playing too short in his shots.

"Yes, he hit the ball very hard, very flat.  But at the same time, probably for moments I played too short, no?  If I'm able to play longer, to play a little bit higher or longer, he takes a lot of risk in every shot," Nadal said.

"Playing from more difficult positions, in my opinion, he will not have that success that he had in the second set, no?  So my opinion was more my fault.  But he was in the match until then," he added.

Nadal's victory against Gojowczyk on Friday put him one win away from bagging his first tournament win of the season after capturing 10 titles - including the French and U.S. Open crowns - last year. Standing in his way to glory will be the winner of the other semifinal pairing between Florian Meyer and Gael Monfils.