TENNIS: Rafael Nadal OUT of Italian Open after quarter-final defeat against Stan Wawrinka

Rafael Nadal's crisis of confidence was compounded on Friday night when Stan Wawrinka sent him packing from the Italian Open.

The nine-times Roland Garros champion was beaten 7-6, 6-2 in the quarter-finals by the Swiss No 2, heaping up the problems for the Spaniard ahead of his latest Roland Garros defence that begins a week on Sunday.

Nadal, beaten by Andy Murray in the Madrid final last Sunday, has not struggled like this before on the clay since his reign as the king of Paris began. 

Rafael Nadal gestures to the umpire during his straight sets defeat against Stan Wawrinka

Wawrinka celebrates condemning Spanish star Nadal to his fifth clay court defeat of the season

Most alarming was his subsidence in the tiebreak, which he led 6-2 before being dramatically pegged back by the Swiss, who was to take it 9-7. 

After an early break in the second set Wawrinka held on and Nadal will now go to Paris without a European clay court title this year. 

One by product is he will be seeded outside the top four in Paris and, probably, for Wimbledon.

Nadal said after his defeat: 'I didn't have enough leg in some moments today. He (Wawrinka) played crazy. He hit amazing shots in a lot of moments, and especially important ones.' 

He added: 'At 6-2 he played a lot of good points. I am not very happy with the way I played.' 

Nadal, beaten by Andy Murray in the Madrid final last Sunday, looks on in disappointment after the match

American actor Ben Stiller (centre) was in attendance to watch the action unfold in Rome

Wawrinka will now face Swiss compatriot Roger Federer in the Italian Open semi-finals

Novak Djokovic had earlier stormed into the semi-finals but still Roger Federer is in no doubt who will go into the French Open as the favourite, despite Nadal'a apparently fading superiority.

'Regardless of what anybody says to me Rafa is the favourite for the French Open,' commented Federer, who will play his compatriot Wawrinka.

'The guy has lost only one match at Roland Garros in ten years, so there's absolutely no way you pass that guy in being the favourite for that tournament.'

Novak Djokovic celebrates after booking his place in the semi-finals of the Italian Open on Friday

Serbian star Djokovic plays a forehand as the world No 1 beats Kei Nishikori in straight sets

Federer was hugely impressive himself in beating world number six Tomas Berdych 6-3 6-3 to make it to the last four.

Djokovic was forced to go three sets once more before blasting his way into the other semi-final, where he will meet David Ferrer.

Having needed to come back from a set down to beat Brazilian Thomas Bellucci on Thursday night he was pushed to another decider by number five seed Kei Nishikori.

Despite not having played his best the world number one accelerated through it as the Japanese subsided disappointingly to a 6-3, 3-6, 6-1 defeat.