Stefanos Tsitsipas continued his strong run of form en route to the Miami Open third round, while Aslan Karatsev's maintained his fairytale run in 2021.

Greek star Tsitsipas flexed his muscles in a straight-sets win over Damir Dzumhur on Saturday.

Australian Open semi-finalist and Dubai Tennis Championships winner Karatsev enjoyed a victorious Miami debut.

Andrey Rublev, Diego Schwartzman, Denis Shapovalov, Marin Cilic and Milos Raonic also progressed at the ATP 1000 tournament.

TSITSIPAS STAYS HOT

World number five Tsitsipas eased past Dzumhur 6-1 6-4 in his first appearance since losing in last week's Mexican Open final.

Tsitsipas (15-4) became the third player to reach 15 wins this season, the second seed following in the footsteps of Russian duo Rublev (17-3) and Daniil Medvedev (15-2).

"It was a great match, especially against a guy that I probably don't have a good record playing against in the past," said Tsitsipas. "I started the match very strong, breaking him twice and taking a big lead in the score, and I think the things worked out by themselves after that."

Tsitsipas will face Kei Nishikori after the Japanese outlasted Aljaz Bedene 7-6 (8-6) 5-7 6-4.

NO STOPPING KARATSEV

Karatsev's Miami Open debut ended in a 6-4 6-3 win for the 17th-seeded Russian over Mikhail Kukushkin.

Already in the ATP's top 100 and set to keep climbing, Karatsev broke serve four times en route to the next round, where Sebastian Korda awaits after upstaging 10th seed Fabio Fognini 1-6 6-4 6-2.

"Of course it gives me confidence to win my first title, but you arrive here and it’s a different surface and new tournament," said Karatsev, who ended last season ranked 112th before bursting into the top 30 behind his semi-final run at Melbourne Park. "So you try [to think of it] as a new tournament and new place, but of course it gives me a lot of confidence."

Karatsev owns a 13-2 record this year, with his only two losses coming against world number one Novak Djokovic and US Open champion Dominic Thiem.

RUBLEV ROLLS ON

Fourth seed Rublev has proven to be remarkably consistent, highlighted by his crushing 6-1 6-2 rain-interrupted victory against Tennys Sandgren.

Having equalled his previous best run in Miami, Rublev will play 29th seed Marton Fucsovics who took down Thanasi Kokkinakis 7-6 (7-3) 6-7 (4-7) 6-4.

Rublev has won a Tour-leading 17 matches this year.

Elsewhere, fifth seed Schwartzman was a 6-3 6-3 winner against Yasutaka Uchiyama, Shapovalov – the sixth seed – trumped Ilya Ivashka 6-7 (5-7) 6-4 6-4 in a marathon, 12th seed Raonic accounted for Jordan Thompson 6-2 6-1, former US Open winner Cilic surprised 13th seed Christian Garin 3-6 7-5 7-6 (7-5), while 15th seed Alex de Minaur was eliminated.