Unseeded American Bernarda Pera flew out of the blocks at the Australian Open on Monday and trounced three-times Grand Slam champion Angelique Kerber 6-0 6-4 to storm into the second round.
Compatriot Venus Williams, a finalist at Melbourne Park in 2003 and 2017, also enjoyed a winning start at Margaret Court Arena, advancing with a 7-5 6-2 win over Kirsten Flipkens.
Kerber, Australian Open champion in 2016, came into her first meeting with Pera as the favourite but won just eight points en route to conceding the first set in 18 minutes.
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Pera broke the 23rd seed early in the second set to take a 3-0 before Kerber finally got on the board with a service break of her own.
The match briefly looked like it was developing into a genuine contest as Kerber traded blows with the American from behind the baseline to fight back to 5-4 but Pera held her nerve to close out the contest.
"I knew that I had a tough opponent but I was ready for it," Pera said in an on-court interview. "She's great fighter. It was probably not her greatest match.
"The first set-and-a-half I played my game and then she fought a little bit better towards the end of the second set but I am happy to get the win."
Highlights | Kirsten Flipkens - Venus Williams
Williams used all of her vast experience to keep things tight against Flipkens, the 40-year-old making just 13 unforced errors compared to 30 from her Belgian opponent.
Flipkens had come into the tournament nursing an ankle injury she picked up last month and said she was still not at her best.
"After all the circumstances I have been through the last couple of weeks with my injury I cannot expect to bring out my best level, but Venus played a good match in general," she said.
"I think once you give her an opportunity, she's taking it."
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