Extreme heat, then rain, cause big delays at Australian Open

Andy Murray ousts No. 13 Matteo Berrettini in 5-set thriller (0:57)

Andy Murray advances to the second round of the Australian Open with a victory over No. 13 Matteo Berrettini. (0:57)

MELBOURNE, Australia -- Extreme heat, followed by monsoonal rain, caused significant delays during Day 2 of the Australian Open, resulting in 19 matches having to be rescheduled to Wednesday.

Play had been stop-start for much of the day at Melbourne Park, but it was eventually called off on the outside courts shortly before midnight after what was a fourth rain interruption. It left several players agonizingly short of victory.

Croatia's Donna Vekic was potentially just two points away from wrapping up her match against Oksana Selekhmeteva on Court 15, while Australian Thanasi Kokkinakis left Kia Arena requiring just five more points against Italian journeyman Fabio Fognini. These matches, along with the nine others that were postponed, will resume on Day 3 in Melbourne, while the other eight clashes, which never commenced, will also be played in addition to what was already slated for Wednesday.

Earlier, the Denis Kudla-Roman Safiullin and Richard Gasquet-Ugo Humbert matches were shifted ahead a day, ensuring no player received an unfair rest advantage ahead of the second round. The reshuffling of the schedule also saw local Alexei Popyrin and Taipei's Chun-Hsin Tseng moved to the undercover stadium of John Cain Arena.

Play on all outside courts was first suspended just after 2 p.m. in Melbourne, with the mercury hitting 37 degrees C (90 degrees F) and tournament organizers opting to enforce the extreme heat policy.

"The AO Heat Stress Scale has reached five and play will be suspended on the outside courts," Tennis Australia released in a statement. "Play continues until the end of an even number of games or the completion of a tiebreak. Play on outdoor practice courts is also suspended."

The heat stress scale, which measures radiant heat, air temperature, wind speed and humidity, was introduced in 2019 after several players had issued complaints about a lack of consistent guidelines around competition in oppressive heat. It features stages one through five, with lower stages allowing for the implementation of cooling strategies and improved hydration while play is suspended immediately once the maximum of five is hit.

Matches continued on the three main show courts of Rod Laver Arena, Margaret Court Arena and John Cain Arena, after brief delays to close roofs.

Play on the 12 outside courts resumed around 5 p.m. once conditions had improved. But it was short-lived, as a sudden dip in temperature at 7:45 p.m. brought an extended downpour, further suspending the first-round action at Melbourne Park with 27 matches still to be decided.

Showers eventually eased after 90 minutes, and play was set to resume before more precipitation arrived and players once again left the courts. Another rain stoppage was called at 10:30 p.m, before all outside courts were listed as "closed."

Rain remains a threat in Melbourne on Wednesday, which could lead to further delays.