Del Potro returns with ATP win in Mexico

Juan Martin del Potro opened his northern hemisphere summer hard-court season with a 7-5 6-3 victory over American Marcos Giron on Wednesday night in the Mifel Open.

Playing for the first time since losing to Rafael Nadal in the Wimbledon quarter-finals, the top-seeded del Potro set up a quarter-final match against Egor Gerasimov.

Del Potro won hard-court titles this year at Indian Wells and Acapulco.

The fourth-ranked Argentine star has 22 career victories, the biggest on a hard court in the 2009 US Open.

Gerasimov, from Belarus, outlasted fifth-seeded defending champion Sam Querrey of the United States 7-5 5-7 7-6 (8-6).

Fourth-seeded Adrian Mannarino of France topped Sweden's Elias Ymer 6-0 6-2.

The Frenchman will play Cameron Norrie, the British left-hander coming off a semi-final appearance in Atlanta.

Norrie beat eighth-seded Feliciano Lopez of Spain 6-3 6-3.

Japan's Yoshihito Nishioka also knocked off a seeded player, topping seventh-seeded Taylor Fritz of the United States 7-6 (7-3) 6-1.

Nishioka will face second-seeded Fabio Fognini of Italy.

Third-seeded Damir Dzumhur of Bosnia and Herzegovina got past Italy's Thomas Fabbiano, 7-6 (7-0) 7-6 (7-5).

He'll play American Michael Mmoh, a 7-6 (7-1) 7-6 (7-2) winner over Canada's Peter Polansky.