JOIN USFormer US Open champions Marin Cilic and Juan Martin del Potro powered into the fourth round of the Miami Open on Sunday with straight-sets victories.
Argentina's fifth-seeded del Potro, chasing his second ATP Masters title in as many weeks, breezed past Japan's Kei Nishikori 6-2, 6-2.
Ranked sixth in the world after vanquishing Swiss great Roger Federer in the final at Indian Wells last weekend, del Potro needed just 73 minutes to book a fourth-round meeting with Filip Krajinovic of Serbia, who beat France's Benoit Paire 6-3, 6-3.
Second-seeded Cilic also reached the fourth round with a 7-5, 7-6 (7/4) victory over Canadian Vasek Pospisil.
Cilic produced six aces and saved all three break points he faced. But Pospisil made him work to finish it off, save three match points on his own serve in the 12th game of the second set.
Cilic will face 14th-seeded American John Isner for a quarterfinal berth. Isner defeated Russian veteran Mikhail Youzhny 6-4, 6-3.
Third-seeded Grigor Dimitrov of Bulgaria joined the exodus as he fell 6-4, 6-4 to unseeded Frenchman Jeremy Chardy.
Del Potro, the hottest player on the ATP tour right now, is actually in search of a third straight ATP crown after back-to-back victories in Acapulco and Indian Wells.
"I think I'm playing good," Del Potro said after his 13th straight match win. "I can play even better, but I need to get confidence playing in this court, trying to keep winning matches.
"But it's not easy," he added. "My body starts to feel tight because of all my success."
In other third-round action, South Korean Chung Hyeon posted a convincing 6-1, 6-1 victory over American qualifier Michael Mmoh.
Chung, who has yet to drop a set in Miami, needed just 63 minutes to advance to a meeting with Portugal's Joao Sousa, who rallied for a 1-6, 6-3, 6-4 win over American Jared Donaldson.
Venus outlasts Bertens
Three-time winner Venus Williams saved three match points in a three-set victory over Kiki Bertens on Sunday, lining up a fourth-round clash with reigning champion Johanna Konta.
Venus, ranked eighth in the world, labored nearly three hours to beat 29th-ranked Bertens 5-7, 6-3, 7-5.
"It didn't look good sometimes, that's why you keep playing until the last point," said Venus.
Konta, whose victory here last year propelled her into the top 10 in the world rankings, advanced with relative ease, beating Belgian Elise Mertens 6-2, 6-1.
Fourth-seeded Elina Svitolina and sixth-seeded Jelena Ostapenko, the reigning French Open champion, also advanced, as did 2016 Olympic gold medalist Monica Puig.
Ukraine's Svitolina beat Daria Gavrilova 4-6, 6-0, 6-1, her fourth straight win over the Australian.
In a match of tense rallies, Svitolina finished with 28 winners and won 70 percent of her first-serve points.
Svitolina will battle for a quarterfinal berth against another Australian, 21st-seeded Ashleigh Barty, who beat Croatia's Petra Martic 6-4, 6-3.
Latvian Ostapenko defeated Brazilian Beatriz Haddad Maia 6-2, 7-6 (7/2).
Puerto Rico's Puig followed up her upset of second-seeded Australian Open champion Caroline Wozniacki with a 6-3, 7-5 victory over Greece's Maria Sakkari.