MIAMI GARDENS: World number three Jessica Pegula got her Miami Open campaign under way with a confident 6-3, 6-1 second round win over Canada's Katherine Sebov on Thursday.
With top-ranked Iga Swiatek having withdrawn, American Pegula is among the favourites to challenge Aryna Sabalenka for the title.
"I had to adjust my game plan a little bit in that first set and then was able to close it out pretty easily," said Pegula, a semi-finalist in Miami in 2022.
Pegula will face fellow American Danielle Collins in the second round after she beat Bulgarian Viktoriya Tomova 7-6 (7/3), 6-2.
"She is someone who is pretty tough to play against and on a fast court as well, she will be going for her shots and playing aggressive. She's feisty, she competes really well. It's going to be a tough match," said Pegula.
Belgium's Elise Mertens upset eighth seed Daria Kasatkina 4-6, 6-2, 6-2.
After letting a 3-0 advantage slip in the first set, Mertens dominated as Kasatkina struggled physically, needing a medical time-out in the second set.
Spain's Paula Badosa battled to a 7-6 (7/2), 4-6, 6-3 win over Germany's Laura Siegemund while Russian Anastasia Potapova defeated Ukrainian Marta Kostyuk 6-1, 6-3.
Kostyuk, enjoying plenty of support on the small outer court from Ukrainian fans gathered behind national flags, was never able to put her opponent under pressure.
There was no handshake from the two players at the end of the game as they left the court without acknowledging each other.
Potapova had generated some controversy and was formally warned by the WTA after wearing a Spartak Moscow football shirt before a game at Indian Wells
In first round ATP action, big-hitting Czech Jiri Lehecka cruised to a 6-3, 6-4 win over Argentine Federico Coria.
"The conditions suit me much better than in Indian Wells,” Lehecka said.
"The surface is a bit faster and the balls are flying more. I managed it well and I am super happy to get the win," he added.
Chile's Cristian Garin beat American Marcos Giron 6-4, 2-6, 6-4 and will face Argentine Sebastian Baez next.
World number one Carlos Alcaraz starts his campaign on Friday against Argentine Facundo Bagnis.