Australian Open reigning champion beats world No 85 by 4-6, 6-3, 6-4, 6-4

Italian makes most of suspension in play in win at Melbourne Park

The grim expression across Jannik Sinner’s face as he limped gingerly to the bathroom said enough. As play was briefly suspended in the overbearing Australian heat, the two-time defending champion was suffering from full-body cramps and at serious risk of also enduring one of the great Australian Open upsets in recent memory.

Sinner, the second seed, survived thanks to the combined force of his supreme mental toughness and a significant amount of luck, holding off a spirited challenge from Eliot Spizzirri to reach the fourth round at Melbourne Park with a 4-6, 6-3, 6-4, 6-4 win.

The straightforward scores in the final three sets belie the drama that unfolded on Rod Laver Arena. On the hottest day of the tournament so far, Sinner struggled badly in 36C heat against Spizzirri, a 24-year-old American ranked No 85 and in the main draw of a grand slam tournament for just the third time in his career.