Miomir Kecmanovic, Serbia, def. Tristan Schoolkate, Australia, 6-2, 6-2.
Alejandro Davidovich Fokina (4), Spain, def. Daniel Altmaier, Germany, 7-5, 6-3.
Brandon Nakashima, United States, def. Elias Ymer, Sweden, 6-3, 6-4.
Patrick Kypson, United States, def. Alex de Minaur (2), Australia, 6-1, 6-7 (4), 7-6 (4).
Valentin Vacherot (6), Monaco, def. Coleman Wong, Hong Kong, China, 4-6, 6-3, 6-2.
Miguel Angel Reyes-Varela, Mexico, and Nuno Borges, Portugal, def. Edouard Roger-Vasselin, France, and Hugo Nys (2), Monaco, 6-3, 6-3.
Grigor Dimitrov, Bulgaria, and Flavio Cobolli, Italy, def. Luke Johnson, Britain, and Jan Zielinski (4), Poland, 7-6 (6), 2-6, 10-8.
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