Russia s Daniil Medvedev, left, reacts after losing against Brazil s Thiago Seyboth Wild, right, during their first round match of the French Open tennis tournament at the Roland Garros stadium in Paris, Tuesday, May 30, 2023. Photo: AP
Seyboth Wild, who came through the qualifiers and had never previously won a Grand Slam match, triumphed 7-6 (7/5), 6-7 (6/8), 2-6, 6-3, 6-4.
It was Medvedev's fifth loss in the opening round at Roland Garros in seven appearances.
"I have watched Daniil play in my junior years. It's a dream come true to beat these kinds of players on this court," said the 23-year-old Brazilian who unleashed 69 winners past the Russian.
"I just wanted to get my angles right, get to the net as much as possible and use my forehand as much as possible against his -- I guess it worked pretty well."
He added: "I was cramping in the second set and couldn't really serve the way I wanted to but I tried to play my best tennis. I'm really happy with the way I played."
Seyboth Wild, without a win on the main tour since February 2022, had squandered two set points which would have given him a two-sets lead.
Medvedev made him pay, levelling the tie and then claiming a double break in the third set.
But the Brazilian hit back, a double break of his own in the fourth set levelling the clash as a fractious Medvedev bickered with the crowd.
In the final set, Seyboth Wild twice saw breaks retrieved by the Russian before he finally backed up a third break with a hold for 5-3.
He held his nerve to clinch the four-hour 15-minute match courtesy of two giant forehands and will face either Guido Pella or Quentin Halys for a place in the last 32.
Medvedev arrived in Paris buoyed by winning his first ever clay court title at the prestigious Italian Open last week for his fifth trophy of 2023.
But he has endured a bitter-sweet relationship with the French Open, losing in the first round in his first four visits. He ended that streak with a run to the quarter-finals in 2021.
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