Serena Williams chose to go home and Victoria Azarenka was sent home during Wednesday's upheaval at the French Open in Paris.
Williams withdrew from her second-round match against Bulgaria's Tsvetana Pironkova due to her Achilles injury, while U.S. Open finalist Azarenka was easily handled in straight sets by Slovakia's Anna Karolina Schmiedlova.
Three-time French Open champ Williams tested her leg prior to the match at Roland Garros and quickly realized she would be unable to play, ending her pursuit of tying Margaret Court's record of 24 Grand Slam titles.
"I really wanted to give an effort here. It's my Achilles that didn't have enough time to properly heal after the Open," Williams said at her news conference. "I was able to get it somewhat better, but just looking long term in this tournament -- will I be able to get through enough matches? For me, I don't think I could. Struggling to walk, so that's kind of a telltale sign I should try to recover."
The sixth-seeded Williams suffered the injury during her U.S. Open semifinal loss to Azarenka on Sept. 11.
It was a rough day on the clay for the 10th-seeded Azarenka, who was outplayed by Schmiedlova. Azarenka, from Belarus, racked up 38 unforced errors as Schmiedlova rolled to a 6-2, 6-2 triumph.
"The lesson I need to learn is that sometimes when things don't work for me, the way I was playing today was just not the right time, was to be willing to adjust a little bit more and not think kind of in the end of the match to finally start changing your kind of my game," Azarenka said afterward.
"I felt like I was trying a lot, trying different things, but today things were not working. I felt like nothing really was working, but I still had to find a way to win, and I didn't."
Schmiedlova, ranked 168th, entered the French Open with a 13-match losing streak in Grand Slam events since last prevailing in the 2015 U.S. Open.
Top-seeded Simona Halep advanced by defeating fellow Romanian Irina-Camelia Begu 6-3, 6-4.
Third-seeded Elina Svitolina of Ukraine knocked off Mexico's Renata Zarazua 6-3, 0-6, 6-2. The match was briefly interrupted by a loud bang that was eventually determined to be a sonic boom produced by a fighter plane.
Fifth-seeded Kiki Bertens of Netherlands had to fight off Italy's Sara Errani 7-6 (5), 3-6, 9-7. Bertens had 61 winners and Errani committed 14 double-faults in a match that took three hours and 11 minutes.
Elise Mertens, the No. 16 seed from Belgium, was a 6-4, 7-5 winner over Kaia Kanepi of Estonia. No. 25 Amanda Anisimova cruised past Bernarda Pera 6-2, 6-0 in a battle of Americans.
Others who advanced include No. 20 Maria Sakkari of Greece, No. 23 Yulia Putintseva of Kazakhstan, No. 27 Ekaterina Alexandrova of Russia and No. 32 Barbora Strycova of the Czech Republic.
--Field Level Media