Australia’s Ash Barty has won through to the second round of the Australian Open, but only after a scare when beaten in the first set by Lesia Tsurenko of the Ukraine.

The World No.1 lost the first set 7-5 before blitzing her 30-year-old opponent to take the last two sets 6-1 6-1.

Barty was unfazed by the slow start, telling Channel Nine that she just needed to finetune her game

“It’s all good,” she laughed.

“No, look, it’s amazing to be back out here. Obviously it is a tight turn around from Adelaide, but really nice to kind of sort it out a little bit more and at the start of the second set sharpened up and did what I needed to do.”

Barty said she had been looking forward to getting out in front of her home fans at Australia’s biggest event.

This is probably the moment I have been looking forward to the most through the off-season. I couldn’t wait to walk out here on this beautiful court in front of so many people that give me such love and support.

“I think in the first set it was still in my control. It was just a little bit of execution. I was just rushing a little bit, trying to finish off points too early.

“Once I was able to get my physicality into it, I felt a lot more comfortable and I think I was able to go get – you know, look after my service games a little better and not get behind in the set, which was important.”

Earlier on Monday night Sam Stosur’s run of Australian Open first-round losses stretched to five straight years with the veteran falling to American qualifier Caty McNally.

In a repeat of last year’s first-round shocker, Stosur had no answer to the talented 18-year-old, going down 6-1 6-4 to continue her painful run at the first grand slam of the year.

Five in a row: Sam Stosur after losing her first-round Australian Open match on Monday.

Playing in her first Australian Open, world No.116 McNally looked fearless as she attacked Stosur’s big serve and also delivered some strong net play.

Former US Open champion Stosur, who is now ranked 99, was hampered by 39 unforced errors that effectively brought undone her 18th Melbourne Park appearance.

Stosur had a chance to get back into the match in the second set, breaking back and then levelling at 4-4.

But McNally held serve before breaking the 35-year-old again to take the victory.

Stosur’s loss continued a mostly miserable opening day for the Australian contingent.

Wildcard Lizette Cabrera admitted her American opponent Ann Li was braver when it mattered most after letting a golden opportunity for a maiden Australian Open victory go begging.

Wildcard Lizette Cabrera had some good moments, but lost. Photo: AAP

The 22-year-old Australian served for both sets against the US qualifier in the opening round but was broken on each occasion in the 7-6 (7-4) 7-6 (12-10) loss.

The 22-year-old showed plenty of pluck in the second-set tiebreak, saving five match points before Li finally claimed the victory on her grand slam debut after a brief rain delay.

“I was pretty disappointed with today’s match,” Cabrera told AAP.

I did have a lot of opportunities. Ann’s a good friend, she played really well and was braver in the bigger moments. But I’m still happy with the way I competed and fought even though it wasn’t my best tennis.’’

Fellow Australians Andrew Harris and John-Patrick Smith also crashed out at the first hurdle.

Harris, the 25-year-old son of former Australian Open quarter-finalist Anne Minter, bowed out 6-3 6-1 6-3 to Italian No.8 seed Matteo Berrettini.

Harris was awarded a wildcard to the Open after enjoying a career-best 2019 campaign in which his ranking was slashed from 400 to 162.

Smith was also beaten in straight sets.

The 30-year-old wildcard playoff winner lost 6-3 7-5 6-4 to No.22 seed Guido Pella from Argentina.

Smith has now lost all six of his main-draw singles matches at the majors.

-with AAP