Paris - Argentina's Leonardo Mayer said he could have played "20 sets" against "mountain" Roger Federer at Roland Garros on Sunday and still not have won any.
The 32-year-old Mayer lost 6-2, 6-3, 6-3 to Federer in the last 16, his fourth defeat in four meetings with the great Swiss player.
"If today we played 20 sets I would not have won one, I was very far from my level," said the world number 68.
"It was a very strange day, I didn't play well and I saw him as a mountain."
Results from the eighth day of the French Open on Sunday (x denotes seeding):
Stan Wawrinka (SUI x24) bt Stefanos Tsitsipas (GRE x6) 7-6 (8/6), 5-7, 6-4, 3-6, 8-6
Roger Federer (SUI x3) bt Leonardo Mayer (ARG) 6-2, 6-3, 6-3
Kei Nishikori (JPN x7) leads Benoit Paire (FRA) 6-2, 6-7 (8/10), 6-2 - match suspended due to darkness
Rafael Nadal (ESP x2) bt Juan Ignacio Londero (ARG) 6-2, 6-3, 6-3
Sloane Stephens (USA x7) bt Garbine Muguruza (ESP x19) 6-4, 6-3
Johanna Konta (GBR x26) bt Donna Vekic (CRO x23) 6-2, 6-4
Marketa Vondrousova (CZE) bt Anastasija Sevastova (LAT x12) 6-2, 6-0
Petra Martic (CRO x31) bt Kaia Kanepi (EST) 5-7, 6-2, 6-4