Madrid:Top seed Rafael Nadal has defeated Czech Republic's Radek Stepanek to enter the semifinals of the Madrid Masters Series event. The Spanish world number two survived two set points in a first set tiebreaker before taking it 11-9. He then broke the number ten seed's serve in the ninth game to win 7-6, 6-4 in an hour and 52 minutes. In another quarterfinal match, fifth seed Argentina's David Nalbandian filled the final berth in the last four after defeating Croatia's Ivo Karlovic 6-4, 7-6 (4). While Nalbandian will meet Croatia's Ivan Ljubicic in the semi-finals, Nadal will face Robby Ginepri of the United States. Nadal had won all three of his previous encounters with Stepanek, two of which came earlier in the season. But on this occasion in a thrilling match, Stepanek stood firm forced a tiebreaker and gained two set points along the way. However, Nadal managed to save both and then stepped up a gear with a stunning backhand pass on the run which brought the crowd to their feet. In the end, the tiebreak was won by the Spaniard 11-9. Nadal broke the Czech's serve in the ninth game of the second set and finished the match on his third match point 7-6 (9), 6-4 in an hour and 52 minutes. It was Nadal's 77th win of the year, equalling Roger Federer's record for 2005.