MADRID (AFP) - Rafael Nadal shrugged off a pre-match shoulder injury scare to squeeze into the semi-finals of the Madrid Masters on Friday, beating close friend and compatriot Feliciano Lopez 6-4, 6-4. The top seed, and 2005 champion, revealed that he had taken treatment on his problem shoulder joint until shortly before the match. "It was a tough situation and I'm very glad to get this win," said the man who can claim the year-end number 1 ranking by reaching Sunday's final, according to ATP calculations. Nadal will face off for a place in the final when he takes on Frenchman Gilles Simon, who defeated Ivo Karlovic 7-6 (7/1), 4-6, 7-6 (7/2) in the face of 27 aces from the Croatian. Andy Murray and Roger Federer earlier set-up a re-run of last month's US Open final as they ploughed to straight set victories. Losing New York finalist Murray led the way with his 6-2, 6-2 thrashing of Frenchman Gael Monfils, with second seed Federer storming past rising Argentine Juan Martin Del Potro 6-3, 6-3. "I served well and didn't get broken so I'm happy with my game at the moment," said Federer who is playing this week after a three-week break from the game in order to rest. "I did well and chose the right tactics." Murray and Federer stand 2-2 in their series, with the Scottish youngster winning in Dubai and Federer lifting his 13th Grand Slam singles title at Flushing Meadows in their second meeting this season. "I like playing Andy, he's an interesting player," added Federer. "He's a great tactician, you have to come in with a proper game plan. "He's playing well, and played a good match against Monfils. I'll have my hands full against him." Since Wimbledon, world number four Murray has played his way into the last four at every event he's entered save the Beijing Olympics, where he lost in the first round. "I've done very well since the summer but it's not a given that I'll always make it to the weekend," said Murray. "But I've had a good season." "In other years, the points I have would have been good enough for number two in the world. It just that we have the best two top guys ever and (Novak) Djokovic has been playing very consistently in front of me (on third in the rankings). "I just want to try and keep my form for the big events," said the winner of the previous Masters in Cincinnati last August. Federer saved the only break point he faced in 1hr 28min while breaking Del Potro three times. The Swiss now stands 3-0 after beating the South American twice in 2007. Murray improved to 2-1 over Monfils, coached by Lleyton Hewitt's former mentor Roger Rasheed who has instilled training discipline into the free-spirited French youngster. But the new regime was not enough to make a difference on the day, with Monfils ending on a double-fault, his 31st unforced error of a 67-minute afternoon. Murray struck 17 winners and 19 errors, breaking on six of his 11 chances. The loss left Monfils adrift as he aims for a long-odds place in the eight-man season-ending Masters Cup in Shanghai, standing 14th with two weeks of ATP play remaining. Murray has already qualified along with Federer, Rafael Nadal and Novak Djokovic with four spots still open.