Spain's Jaume Munar disappointed the fans at the Cordoba (Argentina) Open on Wednesday, upsetting top-seeded Argentinian Francisco Cerundolo 7-5, 6-4 in second-round action.
Munar repeatedly got into and out of trouble, saving 10 of 12 break points while beating Cerundolo for the first time in three career matchups.
In the quarterfinals, Munar will oppose Argentina's Facundo Bagnis, who beat eighth-seeded Spaniard Roberto Carballes Baena 7-6 (5), 6-4.
The day's other two second-round matches also saw Argentinians defeat Spaniards. Third-seeded Tomas Martin Etcheverry got past Bernabe Zapata Miralles 7-5, 6-4, and Federico Coria routed Albert Ramos-Vinolas 6-1, 6-3.
Open 13 Provence
Third-seeded Karen Khachanov of Russia needed just 76 minutes to get past Spain's Roberto Bautista Agut 6-2, 6-2 in the second round at Marseille, France.
Khachanov compiled a 14-5 edge in aces and dominated on key points, taking advantage of four of his five break opportunities.
The Czech Republic's Tomas Machac pulled off a second-round upset, downing sixth-seeded Lorenzo Musetti of Italy 6-3, 6-2. Fourth-seeded Ugo Humbert won an all-French match against Hugo Gaston 2-6, 6-1, 6-3. Seventh-seeded Felix Auger-Aliassime of Canada defeated France's Quentin Halys 6-2, 7-5, and Finland's Emil Ruusuvuori edged France's Luca Van Assche 7-6 (2), 6-4.
Dallas Open
Third-seeded Ben Shelton, playing in the event for the first time in his career following an opening-round bye, prevailed 6-3, 6-3 over Michael Mmoh in an all-U.S. second-round match at Dallas.
Shelton won 93 percent of his first-serve points (27 of 29) and never faced a break point in the 1-hour, 3-minute win.
Australia's James Duckworth downed fifth-seeded Christopher Eubanks of the United States 7-6 (3), 6-4, while the United States' Marcos Giron upset sixth-seeded Max Purcell of Australia 6-4, 6-3.
Other winners were the United States' Denis Kudla and Australia's Rinky Hijikata.
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