Petra Kvitova was on the receiving end of an upset in the first round of the WTA International in Adelaide as she was surprisingly beaten by wildcard Priscilla Hon on Monday.

Two-time Wimbledon champion Kvitova, who ended 2021 among the world's top 20 players for the first time since 2016, lost in three sets to her Australian opponent 6-7 (4-7) 7-5 6-2. The victory was Hon's first ever against a player in the top 40.

Elsewhere, number three seed Maria Sakkari saw off Slovenia's Tamara Zidansek 6-2 0-6 6-4, while number seven seed Elena Rybakina earned a 6-4 1-6 6-1 win over Storm Sanders.

Leylah Fernandez, the 2021 US Open runner-up, also looked comfortable in a straight-sets victory against Ekaterina Alexandrova, easing past the Russian 6-3 6-4. The 19-year-old will face either number five seed Iga Swiatek or Daria Saville in the next round.

Heather Watson is out after a 6-4 7-6 (7-5) loss to home favourite Ajla Tomljanovic, while in the doubles event, Japanese pair and top seeds Ena Shibahara and Shuko Aoyama were beaten 6-4 6-2 by Victoria Azarenka and Paula Badosa, who will play against one another in the singles on Tuesday.