Alexander Zverev cruised through his first match at the Miami Open, brushing aside wildcard Martin Damm in straight sets.

The German, who has now won his last 15 matches against players outside the Top 100, won 6-2 6-4 in just 70 minutes.

An early break put Zverev in control at 2-0, and he extended his lead further by reeling off three straight games en route to claiming the first set.

Damm put up more of a fight in the second, but the damage was done in the first game as Zverev went a break up straight away and never let go of his lead.

"He's somebody that's extremely dangerous, has a massive serve, massive game," Zverev said of Damm.

"I'm happy with the match, happy with my level, and looking forward to what's ahead."

Ben Shelton, though, suffered another early exit in Miami as Alexander Shevchenko came from behind to earn a 6-7 (3-7) 7-6 (7-3) 6-3 upset.

Both players stayed on serve throughout the first two sets in a tightly fought encounter, but Shevchenko found the edge in the second game of the decider to set him on course to victory.

It is the Kazakhstani's third Top-10 win, while he is through to the third round at an ATP Masters 1000 for the fourth time in his career.

Data Debrief: Zverev keeps piling up records

Zverev claimed his 20th career match win at the Miami Open – it is the fourth ATP Masters 1000 event where he has at least 20 victories, along with Rome (27), Madrid (25) and Paris (20).

He also extended his record for most ATP Masters 1000 wins this decade to 103.

Among currently active players, only Novak Djokovic (420) has claimed more ATP Masters 1000 match wins than Zverev (168).