By Pritha Sarkar
PARIS (Reuters) - Swirling winds caused mayhem and chaos at Roland Garros on Tuesday, with Jo Wilfried Tsonga and Stan Wawrinka emerging unscathed to set up a French Open semi-final.
On a day when Wawrinka would have hoped to bask in the glory of beating his more celebrated rival Roger Federer 6-4 6-3 7-6(4) for the first time on a grand slam stage, it was a freak accident that set the claycourt major abuzz.
Tsonga had whipped the delirious Court Philippe Chatrier crowd into a frenzy as he charged into a 6-1 5-2 lead against Japan's Kei Nishikori when piercing screams were suddenly heard from high up in the stands.
A large rectangular side panel had fallen off from underneath the TV commentary boxes, hitting spectators sitting on the top row.
The incident even caught umpire Carlos Bernardes unaware, as he tried to resume the contest by calling for "Quiet Please" before he realized that everyone was distracted by the mishap which left a silver-haired fan and two others injured.
As the stricken fans were led away by first-aiders, Tsonga and Nishikori were ushered off court for what turned out to be a 40-minute disruption, during which 12 rows of spectators were evacuated and the area cordoned off.
The unexpected break initially did nothing to stall Tsonga's momentum and he returned to finish off Nishikori in the second set.
But after the Japanese hero threatened to gatecrash the French party by roaring back in the next two sets, Tsonga sunk to his knees in triumph as he once again raised hopes of ending France's 32-year wait for a men's Roland Garros champion with a heart-pumping 6-1 6-4 4-6 3-6 6-3 victory.
Gusting winds also proved problematic in the two women's quarter-finals to take place on day 10 of the championships -- but 2008 champion Ana Ivanovic and Czech 13th seed Lucie Safarova weathered the conditions that periodically turned the courts into red dust bowls to set up a last four date.
For men's second seed Federer, however, hopes of a second French Open crown were gone with the wind as he was outplayed, out-thought and out-witted by a rival he had beaten in every one of their previous four grand slam meetings.
Federer's wife Mirka hid her worried eyes behind dark shades and bit her nails ragged as the match neared its inevitable conclusion, with a forehand volley from Wawrinka killing off the 2009 champion's chances of adding to his haul of 17 grand slam trophies.
"Many things... didn't go well, but mostly it's because of Stan's quality of shot making, forehand, backhand, serving big when he had to," said the 33-year-old.
"It was tough. Would have loved to have won the breaker, would have loved to come back in the first set, but wasn't so.
"(The conditions) were tough. So it's impressive the way Stan was able to play."
A day after knocking out 2014 champion Maria Sharapova, Safarova's excitement kept soaring as she stormed into her first Roland Garros semi-final with a 7-6(3) 6-3 win over Spain's Garbine Muguruza.
"It's not easy because you have so many emotions going on... I couldn't really fall asleep yesterday evening, and then I woke up so early," said Safarova, who is bidding to become the first Czech to triumph in Paris since Hana Mandlikova in 1981.
"So I was a little tired in the morning. But the will to win and to be in the semi-finals was so big that once I stepped on the court I was just fighting and playing really well."
Ivanovic's boyfriend, Bayern Munich midfielder Bastian Schweinsteiger, looked far more animated than his Serbian girlfriend when she completed a 6-3 6-2 win over Ukraine's Elina Svitolina .
Whooping and exchanging high-fives with the rest of Ivanovic's entourage in the player's box, Schweinsteiger stood up to give the seventh seed a standing ovation as she reached a grand slam semi for the first time since her 2008 Paris triumph.
"I'm very, very thrilled to be in my first semi-final since 2008. It's been a long road," summed up Ivanovic.
(Reporting by Pritha Sarkar, editing by Toby Davis)