Top-ranked Alcaraz, Sabalenka win Miami openers

"I was really good from the beginning until the last ball," Alcaraz said. "I know how good Joao is and that's why I was really focused, every point, every shot, trying to figure out what is the best possible shot for me."

Alcaraz bounced back from his semi-final loss to Daniil Medvedev at Indian Wells last week to improve to 17-1 in 2026.

That includes an Australian Open title that made him the youngest man to complete a career Grand Slam and a title in Doha.

Alcaraz gained the upper hand against 39th-ranked Fonseca with a break for 2-1 in the opening set, delivering a blistering forehand service return winner on break point.

He closed out the set with a love game, broke Fonseca to open the second and secured the victory with his eighth ace on match point.

It was extra satisfying since Alcaraz was stunned in his Miami opener by David Goffin last year.

"He had a lot of chances to stay in the match to (keep it) tight, so I'm just happy to stay calm, stay positive at these moments," said Alcaraz, who next faces American Sebastian Korda, a 6-0, 6-3 winner over Camilo Ugo.

Women's number one Aryna Sabalenka held off determined American Ann Li 7-6 (7/5), 6-4 to launch her Miami title defense.

The Belarusian was pleased to get through in straight sets against her 39th-ranked foe in a match moved to the third show court as organizers hustled to get the rain-hit tournament back on schedule.

She needed more than an hour to pocket a first set in which she led 4-1 and wasted seven break points in the eighth game.

"I was there, I was fighting no matter what, even though my game probably wasn't the best one that I have," Sabalenka said.

Fourth-seeded American Coco Gauff and sixth-seeded compatriot Amanda Anisimova also reached the third round.

French Open champion Gauff rallied to beat Elisabetta Cocciaretto 3-6, 6-4, 6-3 in a match delayed several hours by rain.

Anisimova outlasted Australian veteran Ajla Tomljanovic 6-1, 5-7, 6-4.

It was Gauff's first match since she retired during her third-round match at Indian Wells with "scary" pain in her left arm.

Gauff said the injury was improving.

"I might feel it sometimes on court, but I definitely feel it less and less every day," said Gauff, who took some time to find her rhythm against the aggressive Cocciaretto.

"She takes the ball so early, you don't have a lot of time to react," Gauff said. "Today, once I got adjusted to the tempo of play I was able to control the rallies when they went the distance."

In other men's action, 56th-ranked American Ethan Quinn upset Norway's 11th-seeded Casper Ruud 6-4, 7-6 (9/7), saving seven set points in the second set on the way to victory.

Japanese wildcard Rei Sakamoto bagged his maiden ATP match win, converting his fifth match point in a 6-4, 3-6, 7-6 (9/7) first-round victory over Aleksandar Kovacevic.

The 19-year-old ranked 164th booked a showdown with in-form Indian Wells finalist Medvedev.

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