DALLAS: Qualifier Jurij Rodionov of Austria defeated sixth-seeded American Maxime Cressy of 7-6(3), 4-6, 6-1 to advance to the round of 16 at the inaugural Dallas Open.
Paris-born Cressy was the first of the eight seeded players to lose his match.
A former UCLA player, Cressy now lives in Hermosa Beach, Calif.
The only other seeded player on the courts was No.7 Marcos Giron of Thousand Oaks, Calif.
Giron, another former UCLA Bruin, defeated countryman Tennys Sandgren 6-4, 6-4.
The former collegiate player at Tennessee has been ranked as high as 41st in the world.
"He's been in the top 50 in the world," Giron said.
He has been ranked as high as No.57.
I knew I would have to play well. I did a good job playing well on the important points."
The top four seeds, all Americans No.1 Taylor Fritz, Reilly Opelka, John Isner and Jenson Brooksby had byes to the round of 16.
On Wednesday, fifth-seed Adrian Mannarino of France will play a round of 32 match and No.8 Brandon Nakashima of the U.S. will play in the round of 16.
Just two of the seven singles matches went to a third set.
Qualifier Cedrik-Marcel Stebe of Germany outlasted American Denis Kudla 7-6(7), 3-6, 6-3 and will face Opelka on Thursday.
Wild card Jack Sock, a Nebraska native, defeated German Oscar Otte 6-4, 6-4.
Sock next will play on Thursday against Fritz, who reached No.20 in the world last month.
Qualifier Liam Broady of Great Britain defeated another German, Peter Gojowczyk, 6-1, 6-4, to advance to the round of 16 against Giron on Wednesday.
Australian Jordan Thompson defeated Spaniard Feliciano Lopez 7-5, 6-3, and will meet Nakashima on Wednesday.
Tuesday's final match went to Yoshihito Nishioka of Japan 6-4, 6-4 over American Mitchell Krueger.
Nishioka will advance to meet the winner of Mannarino's match against American Steve Johnson.
In the doubles draw, Americans Sam Querrey and Jackson Withrow defeated two members of the host SMU tennis team, Adam Neff and Ivan Thamma, 7-6(8), 4-6, 10-5.
SMU captain Caleb Chakravarthi lost his singles match to Canadian qualifier Vasek Pospisil 6-1, 6-0.