It was certainly a day of incident, intrigue, and perhaps even the odd surprise as the first two ATP semifinalists were determined at Roland Garros.

In the battle of the Swiss men, Stan Wawrinka scored his first Grand Slam victory over compatriot Roger Federer as the Swiss No. 2 found the form that showed everyone just how dangerous he could be when he won his maiden Grand Slam at the Australian Open in 2014.

Wawrinka was in control for the first two sets, and hopes were raised as Federer stayed with the pace to push the third set to a tiebreak. One mini-break to Wawrinka was enough to keep him just out of reach, however, with Federer saving one match point before losing the last point on his serve to exit Paris.

“Stan was clutch on the big points and really didn't give me much, so it was a credit to him for playing so well today,” Federer said in his post-match press conference. “I'm already thinking what I'm going to do the next few days, because Wimbledon is going to be a big goal for the season,” he continued.

For Wawrinka, it underlines that he wanted his tennis to do the talking after a less than complimentary article appeared on the Roland Garros official website on the eve of the tournament, bringing forth some strong criticism from the man himself. There was no doubt today that he had set out his case.

“Today was my best match on clay, and it's an incredible moment for me,” said Wawrinka. “I'm playing good tennis and I'm really pleased to be in the Paris semifinals for the first time.”

With perhaps the highest winds we have seen at the tournament, whipping up the top surface of clay like an angry swarm, the winds blew off a part of the scoreboard hoarding. It clattered into the broadcast center before horrifyingly crashing into a section of the crowd, thankfully only injuring three people. When we saw the spikes and the length of the metal panel, it was a miracle that no one was far more seriously injured.

At the time of the incident, Jo-Wilfried Tsonga had steamrolled Kei Nishikori in the first set, and although he took the second set, the delay as the organizers rehoused a section of the crowd was enough to galvanize Nishikori into a comeback, and to temporarily dash French hearts.

After Nishikori erased Tsonga’s two-set lead, the match came down to a final-set shoot-out. With Nishikori battling away with a strapped-up shoulder, and the crowd trying to lift their man, it came down to who would blink first. Tsonga was resorting to deep breathing and meditation to keep his wits together, and it paid off with a break for an advantage he held on to, needing just one match point to make his second semifinal at Roland Garros.

He reached that stage in 2013 and struggled to live up to the occasion against David Ferrer, as they followed what many felt was the de facto final between Rafael Nadal and Novak Djokovic. Now, Tsonga has another chance to become France’s first finalist at Roland Garros since Henri Leconte in 1988. Spelling out ‘Roland, Je t’aime’ and rather sweetly lying down in the ‘T’ shape showed exactly what this meant to him after a delayed start to his season with an injury.

Talking of Djokovic and Nadal, and David Ferrer for that matter, all three are in action on Wednesday. The quarterfinal that everyone has been waiting for will see will have pride of place on Chatrier, with Andy Murray looking for his first clay-court win over Ferrer on Lenglen.

Play starts with the women’s quarter-finals at 2pm CET.