PARIS -- Kristina Mladenovic's first match since her nightmarish end to the US Open produced another collapse and a controversial umpire's call at the French Open on Tuesday.
The French player lost to Laura Siegemund of Germany 7-5, 6-3 after serving for the first set at 5-1.
Mladenovic was furious with chair umpire Eva Asderaki for not spotting a double bounce on set point. During a 10-stroke exchange, Mladenovic hit a drop shot that Siegemund ran for and got back over the net -- although a TV replay showed the ball bounced twice. Mladenovic slowed up, looked confused, and wound up touching the net, which automatically gave the point to Siegemund.
"I think the chair umpire was the only person not to have seen it on the center court," Mladenovic said.
"Mistakes are human but I don't see how the umpire can miss that. She didn't see a double bounce. Unfortunately she will continue at Roland Garros, and I won't continue at Roland Garros."
That point and the first set should have belonged to her right then because of the double bounce, but neither Siegemund, who faced questions of unsportsmanlike conduct, nor Asderaki acknowledged as much.
Mladenovich, however, said the blame lies solely with the umpire.
"If [Siegeman] would have done it, she would have all my respect and be super fair play," Mladenovic said. "But she's not the one responsible. I think the chair umpire is the one that should be really focused on that call."
Siegemund also said it wasn't up to her to make the call, and that she wasn't sure right away whether the ball had bounced twice.
"I can maybe understand a little bit that [Mladenovic] is getting at me, but I think she should get at the umpire. She had plenty of other opportunities," Siegemund said. "I'm coming running full speed. If in that call I say, 'Oh, it was a double bounce,' and later I see on the video it was not, I would be angry at myself."
Mladenovic suggested tennis should start using video replays, like the highly controversial VAR system used in soccer.
"It would be great and we'd avoid a sad scenario like I had today," Mladenovic said.
It wasn't quite as sad as Flushing Meadows, though, where she served for the match at 6-1, 5-1 against Varvara Gracheva then lost a tiebreaker and was crushed 6-0 in the third set.
She called that the most painful loss of her career. Four days later, there was more misery when she was part of the top-seeded women's doubles team dropped from the US Open for having been potentially exposed to COVID-19.
Public health officials who oversaw her tournament hotel said she was at risk after playing cards in a group including Benoit Paire, the Frenchman removed after testing positive for the virus. She had to go into quarantine.
Pliskova, the former top-ranked player, reached the semifinals at Roland Garros in 2017 and next faces Jelena Ostapenko. The big-hitting Latvian player won the French Open that year.
Danish teenager Clara Tauson earned her first tour-level victory by beating US Open semifinalist Jennifer Brady 6-4, 3-6, 9-7. The 17-year-old Tauson, who won the Australian Open junior title last year, saved two match points.
Australian Open champion Sofia Kenin, the fourth seed, got through a three-set test in her first-round match, winning 6-4, 3-6, 6-3 victory in nearly two hours against 125th-ranked Liudmilla Samsonova.
The Associated Press contributed to this report.