US Open finalist Jessica Pegula marked her return from injury with a dominant win over Maria Sakkari at the Adelaide International.

The American top seed took just 73 minutes to claim a 6-4 6-1 win over Greece's Sakkari and move into the quarter-finals of the WTA 500 event.

It was Pegula's first match since she withdrew from the WTA Finals in November with a knee injury.

Pegula reached her first major singles final at September's US Open, where she fell to a straight-set defeat by Aryna Sabalenka.

She will enter the Australian Open, which starts on Sunday, as the seventh seed in the women's singles.

"It's always tough getting the first win of the year, you don't know what to expect," Pegula said.

"But it's good heading into Melbourne next week. My focus is on doing well here first.

"It's fun to problem-solve on court and have a good attitude to start the year."

The 30-year-old will face compatriot Ashlyn Krueger, who beat Spain's Paula Badosa, in the last eight on Thursday.

Meanwhile, Marketa Vondrousova's involvement in the Australian Open has been thrown into doubt after she retired injured from her match against Diana Shnaider.

The 2023 Wimbledon champion, playing in just her second match since undergoing shoulder surgery in August, was leading 6-4 1-1 before tearfully ending the match early.

Tunisia's Ons Jabeur, a two-time Wimbledon finalist, missed out on a place in the quarter-finals as she suffered a 6-2 6-4 defeat by Kazakhstan's Yulia Putintseva.

In the men's event in Adelaide, Canada's fifth seed Felix Auger-Aliassime fought back to beat France's Arthur Cazaux 1-6 6-4 7-5, while top seed Tommy Paul moved past French lucky loser Manuel Guinard 6-4 3-6 6-3.