Del Potro powers past Cilic to set up Nadal semi-final clash

Argentina's Juan Martin Del Potro felled Marin Cilic in a French Open clash of the titans, winning 7-6(5) 5-7 6-3 7-5 on Thursday, and will now aim his heavy artillery at 10-times champion Rafael Nadal in the semi-finals.

Juan Martin del Potro celebrates his win Source: AAP

Del Potro has become one of the biggest threats to Nadal's domination this year, with his pulverising forehand dismantling everyone in his path on the Parisian clay.

After dropping the opening set of his first round match, he won the next 12.

But Cilic, who like Del Potro stands 1.98m tall, owns a US Open title, has a beast of a serve and always looked like being his first serious test. And so it proved.

After returning to a sunny Court Suzanne Lenglen locked at 5-5 in the first set tiebreak after battle was halted because of rain on Thursday morning (AEST), Del Potro flirted with danger before racking up an eighth win in succession against Cilic.

He appeared almost overcome with emotion after reaching his first French Open semi-final since 2009, when he was beaten by eventual champion Roger Federer.

"Well, it's tough to speak," 29-year-old Del Potro, who has risen back to sixth in the rankings after battling back from three left wrist surgeries, said on court as fans sang "Delpo, Delpo".

Asked about facing Nadal, who he has beaten five out of 14 times but never on clay, he was drowned out by his fans.

"It's a challenge that every player wants to have," Del Potro said.

"I don't know if I will win, but I will take big love from you and that's most important for me."