Pavlyuchenkova, who had lost all six of her previous encounters against Pliskova, had a 4-1 lead in the first set and a 2-0 lead in the second before winning the key points in the tiebreaks to clinch victory in two hours and 25 minutes.
Williams, the seven-time Melbourne champion who was seeking a record-equalling 24th Grand Slam title, was stunned by China's Wang Qiang. - Swiss sixth seed Belinda Bencic after joining the exodus of stars from the women's event with a 6-0 6-1 mauling at the hands of Anett Kontaveit.
The Russian sensed early on that if ever she was going to topple her younger nemesis it would be today.
Pliskova said: 'I can play good one match but not really four, five in a row so far.
Pliskova felt she was making mistakes that she would not normally make. "Maybe not huge errors, but I did a lot", she said.
'I still have energy, ambitions, motivation, I'm hungry, I want to achieve bigger things.
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CDC confirmed two cases among travelers returning to Washington state and IL from travels in the Wuhan region of China . Several provinces have been testing patients who meet the proper criteria, but so far, all tests have been negative.
Seattle-Area Voters for voting with smartphones
However, vote-by-mail voters who wait until Election Day to request crossover ballots will have to trade in their mail-in ballots. United States voters overseas can use internet to vote, but they also have to give up their right to a secret ballot.
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The one thing about the Super Bowl is that you'll be hearing about new records being set between now and the start of the game. Neither of Frankie's teams - Buffalo Bills and Los Angeles Rams - are playing, but he will be staying up to watch it.
There are upsets and I think it's normal because, yeah, it's tennis and tennis is very unpredictable. She served six aces to the Russian's five and only had a marginally worse first serve percentage.
He has also benefitted from an easy draw through the first two rounds in Melbourne, defeating a couple of clay specialists in Thiago Monteiro and qualifier Alejandro Tabilo; but he did land his first serve with success (76% and 79% first serve in, with 82% and 86% of first points won).
"It hasn't sunk in yet".
"I don't know what to say, of course I'm really happy but I won't really realise that until later", said Pavlyuchenkova, a quarter-finalist a year ago and in 2017.
Pavlyuchenkova, the No. 30 seed, knocked off No. 2 Karolina Pliskova 7-6 (4), 7-6 (3) to advance to the fourth round of the first Grand Slam of the season.