The signs that things were going horribly wrong for Roger Federer were laid bare at Roland Garros on Tuesday when the Swiss' racket flew out of his grasp after he tripped up and fell to his hands and knees on the red clay.
It is not the graceful manoeuvre one has come to expect from a 17-time grand slam champion who has charmed the world with his wondrous shots rather than clumsy falls.
But that is what Stan Wawrinka reduced his compatriot to on Tuesday -- a fallen champion.
The eighth seed played what he called his "best match in a grand slam" to trump Federer at a major for the first time with a 6-4 6-3 7-6(4) quarter-final victory.
So demoralising was the loss for Federer, who was tipped to reach the final from the half of the draw that did not feature the other members of the Big Four -Novak Djokovic, Rafa Nadal or Andy Murray - that his usually sharp memory also failed him
"I made 30 something errors today. He maybe made one, maybe," said the 2009 champion.
Wawrinka actually produced two more unforced errors than Federer's 26 but it was the winners flying off his racket that caused the real damage -- 43 to 28 from the second seed.
Forever in the shadow of his more celebrated compatriot, Wawrinka channeled all his nervous energy to finally get the better of Federer at a major on his fifth attempt to set up a semi-final date with home favorite Jo-Wilfried Tsonga.
"I was always really, really nervous when I played Roger, especially in a big moment like a quarter-final of a grand slam," the 2014 Australian Open champion said after notching up his third win in 19 meetings with Federer.
"I wasn't really feeling good this morning and before the match but I also knew that's when I play my best game."
Federer's normally smooth rhythm lost all of its usual precision as gusting winds tore through Court Suzanne Lenglen.
He was broken in the third game of the first set, then in the seventh game of the second and when a couple of close calls went against him in the third set tiebreak, his hopes of holding aloft the Musketeers' Cup for a second time were over.
Wawrinka's forehand volley on his second match point propelled him to his first semi-final at the clay court major.