Double defending champion Jannik Sinner advanced to the second round of the Australian Open in just over an hour after his French opponent Hugo Gaston retired upon losing the first two sets 6-2 6-1.
In his first official match since beating Carlos Alcaraz for the ATP Finals crown, the Italian world number two was in ominous form on the Rod Laver Arena court he has ruled for two years before the match was cut short.
After losing the second set, Gaston gestured he could no longer continue and retired to his seat to cry under a towel.
Sinner said he was surprised by the retirement but could see Gaston was not at his best.
Sinner is bidding for a third successive Australian Open crown.
American eighth seed Ben Shelton relied on his power and tiebreak prowess to beat Ugo Humbert 6-3 7-6 (7-2) 7-6 (7-5) in an engrossing battle of left-handers at Rod Laver Arena.
Shelton, who lost to eventual champion Jannik Sinner in last year's semi-finals, blasted through the first set but the Frenchman fought back in the second and third sets to force tiebreaks.
But that was where the American prevailed, counting on his experience from last year when he was involved in eight tiebreaks in six matches at Melbourne Park.
"I thought that I just played two great tiebreakers. I've played a lot of tiebreakers here, a lot of experience, and I think that helped me a lot today," Shelton said.
Australian qualifier Dane Sweeny beat Gael Monfils 6-7 (3-7) 7-5 6-4 7-5 in a match that lasted nearly four hours, knocking out the French veteran in his 20th and final Australian Open/
Monfils, 39, announced he would retire at the end of the 2026 season.
Russian 15th seed Karen Khachanov fired 24 aces and 71 winners as he came out on a top in a near four-hour battle with Alex Michelsen, sealing a 4-6 6-4 6-3 5-7 6-3 victory.
Michelsen had upset Khachanov in straight sets in the third round last year.
Lorenzo Musetti advancedafter his Belgian opponent Raphael Collignon retired while trailing 4-6 7-6 (7-3) 7-5 3-2. Musetti will play fellow Italian Lorenzo Sonego in the second round.
Collignon had given the Italian fifth seed a tough time early on but began cramping towards the end of the third set and retired after the three-hour mark in hot conditions.
Italian 22nd seed Luciano Darderi beat Cristian Garin 7-6 (7-5) 7-5 7-6 (7-3) in just under three hours but did not hang around to celebrate, sprinting to the bathroom immediately after shaking hands with his Chilean opponent.
Darderi had also rushed to the bathroom earlier when Garin needed treatment to his foot.
