June 2 (Reuters) - Joao Fonseca said his run to the French Open quarter-finals had helped him better understand the limits of his game and body after the Brazilian teenager's campaign ended with a defeat by Jakub Mensik on Tuesday.
The 19-year-old fell 6-4 6-3 7-6(3) to the Czech, but said reaching the last eight of a major for the first time had exceeded expectations after arriving in Paris with concerns over a recent injury.
"Coming from a little injury and not having any expectations for this tournament and doing a great run, this is a positive week," Fonseca told reporters.
"This tournament gives me more conviction and more confidence to keep going and for sure understanding a little bit more body and my limits."
Fonseca, who beat Novak Djokovic and Casper Ruud in previous rounds, said the fortnight showed him how his body could cope with the physical demands of Grand Slam tennis and reinforced his belief that he was moving in the right direction.
"I never saw my limit yet, but I already know that I can be comfortable with my physique," he said.
"I think it's more comfortable with my game, the way that I'm playing, that my mentality is on the right path...Maybe it's the same Joao, but finding new stuff."
The teenager was full of praise for 20-year-old Mensik, who advanced to his first Grand Slam semi-final with an impressive display under the closed roof on Court Philippe-Chatrier.
"His serve is amazing," Fonseca said. "The most important thing is he knows how to play in important moments. He's not afraid.
"Today was not me playing bad. It was all his merit."
Despite the defeat, Fonseca said he would head into the grass-court season encouraged by his performance in Paris.
"Looking forward to reset now," he said. "Going back home, enjoy a little bit with the family and then go again for another swing."
(Reporting by Janina Nuno Rios in Mexico City; Editing by Jacqueline Wong)
