PARIS, June 8 — Juan Martin del Potro could be a “nightmare opponent” for Rafael Nadal when they clash in the French Open semi-finals today, according to former champion Mats Wilander. The 29-year-old Argentine, close to his best after battling back from multiple wrist surgeries, reached his first French Open semi-final since 2009 when he downed Croatia’s Marin Cilic in four sets w88 yesterday. Nadal has been untroubled en route to the semis, apart from a blip in the quarter-finals against Diego Schwartzman, but the towering Del Potro looms large on Court Philippe Chatrier today. Del Potro has served 53 aces to reach the semi-final and his forehand, a stroke that could chop down trees, worries the very best as he showed by beating Roger Federer at last year’s US Open and winning the Indian Wells title in March. He has also had success against 10-times French Open champion Nadal, winning five of their 14 matches although never on the Spaniard’s favoured red dirt. They have not played on clay for 11 years, however, so it w88 sports will be a step into the unknown today. “He is a nightmare opponent for Nadal,” three-times French champion Wilander, hosting Eurosport’s flagship Game, Schett and Mats programme at Roland Garros, told Reuters. “He portrays someone who believes in himself as much as Federer, more than (Novak) Djokovic and more than (Andy) Murray. “Sometimes he gets fired up but has this calm about him that I think worries Nadal and Federer. They think, what’s he up to? Has he figured me out? “He is tall so Rafa’s shots don’t bounce over his shoulder, he has big weapons, the serve which gives him free points and m88asia the forehand which is the biggest in the game and he can hit through Nadal’s forehand with it. “Delpo is not afraid of too many players in the world.” The problem for Del Potro might be his backhand which has lost a little sting since his wrist surgeries. “Tomorrow I will try to play a match as I did in a different surface against Rafa,” Del Potro told reporters. “But he’s lefty and he can find easily my backhand, and he knows what my backhand is at the moment. I will try to do my best, to play my best tennis, and see if I m88 mobile can do a good match.” Today’s first semi-final has 72nd-ranked Italian Marco Cecchinato up against Austrian seventh seed Dominic Thiem, the only player to beat Nadal on clay this year and who is bidding to reach his first Grand Slam final after consecutive semis in Paris.