The Miami Masters' top seed, Daniil Medvedev, had no problems making his way past Spain's Pedro Martinez 6-3 6-4 to earn his spot in the fourth round.

Serving was the story of the match as the world number two tallied up 14 aces to his unseeded opponent's zero, and only allowed Martinez to see five second serves in the opening set, with Zverev winning all five. Overall, Zverev won 20 of 24 points on serve in the first set.

The second set was more competitive, with Martinez even breaking back after Zverev jumped ahead and looked to coast to victory, but he could not hold off the Russian down the stretch.

Medvedev will play American Jenson Brooksby in his fourth-round matchup after he won a hard-fought 6-3 5-7 6-4 struggle against 15 seed Roberto Bautista Agut.

In a razor-close contest, Brooksby was just slightly better throughout, winning 60 per cent of his service points compared to the Spaniard's 59 per cent, as well as winning 41 per cent of return points compared to Bautista Agut's 40 per cent.

Fresh off his Indian Wells Masters triumph over Rafael Nadal, Taylor Fritz kept his good form going with a 7-6 (7-2) 6-4 win against American compatriot Tommy Paul.

Fritz, who is now up to world number 13, did not have his serve broken all day, winning 81 per cent of his successful first serves (30-37), while also capitalising on the only two break points he saw.

14 seed Carlos Alcaraz only needed two sets to get past 21 seed Marin Cilic 6-4 6-4, creating nine break point opportunities to Cilic's one, which was saved.

In the late session, and in a meeting of rapidly rising prospects, 22-year-old Serbian Miomir Kecmanovic pulled off an upset 7-6 (7-4) 6-3 win over 21-year-old American Sebastian Korda.

Meanwhile, three seed Stefano Tsitsipas was too much for Australian Alex de Minaur, winning 6-4 6-3 after allowing no break point opportunities in the opening set, and saving all three in the second.