World number three Jessica Pegula powered into the third round of the Australian Open on Wednesday with a straight-sets win over "super-aggressive" Aliaksandra Sasnovich.
Serving for the match at 5-4 in the second set, she was broken by the tenacious world number 38 from Belarus who forced it to a tiebreak.
But that was Pegula's only blip as she got over the line on her second match point to win 6-2, 7-6 (7/5) in 1hr 31min on Rod Laver Arena.
"I thought I played really well," said the American. "I think she really stepped up her level at the end of the second.
"I think I just had to fend off her being really hot and kind of streaky, she was playing super-aggressive but I'm glad I was able to squeak out that second set."
Pegula will face either Australian Olivia Gadecki or Ukraine's Marta Kostyuk in the third round.
The in-form Pegula has reached the quarter-finals on her last two visits to Melbourne Park and is aiming to go deeper this year.
"That's the plan," she said. "You want to take it one match at a time but you want to have those big goals."
Pegula was part of victorious US team at the United Cup two weeks ago where she beat top-ranked Iga Swiatek in straight sets.
"These few weeks that's my main priority, but it's tough out there," she said of going to the latter stages at Melbourne Park.
Pegula also beat Sasnovich in straight sets at the same stage of last year's US Open in the pair's only previous meeting.