(Photo credit: Aaron Doster-Imagn Images)

World No. 8 Taylor Fritz was upset by fellow American Nishesh Basavareddy (ATP No. 156) to headline first-round action of the French Open Sunday at Roland Garros in Paris.

A year after Fritz was upended in the first round at this same event in a shocking upset to German Daniel Altmaier, he repeated the inauspicious feat Sunday, falling to Basavareddy 7-6 (5), 7-6 (5), 6-7 (9), 6-1.

Basavareddy who is into the second round of the French Open for the first time after losing in qualifiers the year prior, withstood 21 aces from Fritz to prevail in three hours and 25 minutes. The 21-year-old converted 3 of 6 break points and kept Fritz unbalanced on the clay court, controlling the net play by taking 31 of 37 (83.8%) opportunities.

'What a match,' Basavareddy said. 'Taylor's obviously a great player, so super happy to get through that, especially after losing the third set. First French Open main draw, and all the support, it's incredible.'

Fritz, the No. 7 seed, stumbled to 48 unforced errors.

Basavareddy advances to face the winner of Kazakhstan's Aleksandar Shevchenko vs. Alex Michelsen, who square off Monday.

No. 2 seed Alexander Zverev of Germany showed no rust in holding off the homecourt advantage of Benjamin Bonzi 6-3, 6-4, 6-2. The World No. 3 made his French Open debut by easing past the Frenchman in two hours, eight minutes.

Zverev is still in pursuit of his first major.

'Very good start to the tournament,' Zverev said following the match. 'It's always nice to start with a straight-sets win, especially against Benjamin, who can cause a lot of problems to top players.

'All around, I think a good performance that I can build on. I have to build on it, but very happy with the start.'

Zverev's next opponent will be Tomas Machac of Czechia, who defeated Belgium's Zizou Bergs 6-4, 6-4, 6-3.

Fritz wasn't alone in getting upset, as Argentina's Tomas Martin Etcheverry, seeded 23rd, lost to Portugal's Nuno Borges 6-3, 6-4, 6-2.

Other seeded winners on Sunday included No. 13 Karen Khachanov of Russia, who coasted past France's Arthur Gea 6-3, 7-6 (3), 6-0; No. 21 Alejandro Davidovich Fokina of Spain, who edged Damir Dzumhur of Bosnia-Herzegovina 6-7 (3), 6-3, 2-6, 7-5, 6-3; No. 26 Jakub Mensik of Czechia who handled France's Titouan Droguet 6-3, 6-2, 6-4; and No. 28 Joao Fonseca of Brazil who controlled France's Luka Pavlovic 7-6 (6), 6-4, 6-2.

Other winners included Australia's James Duckworth Serbia's Miomir Kecmanovic, Argentina's Marco Trungelliti, Argentina's Thiago Agustin Tirante, Croatia's Dino Prizmic and Hamad Medjedovic, Italy's Federico Cina, Belgium's Alexander Blockx and France's Quentin Halys.

--Field Level Media