Nick Kyrgios smashed a racquet and tossed it in the stands on his way to defeat in the Murray River Open Friday as he struggles with injury ahead of the Australian Open.

The Australian showman was hampered by left knee pain during his 6-3, 6-4 loss to Croatia’s Borna Coric and appeared on the verge of pulling out after the first set.

“I can’t serve without pain... when I land it feels unstable,” he told a trainer after the first set.

He opted to continue but was given a warning for swearing then demolished his racquet and threw it into the empty stands when broken on serve.

Coric will play either Briton Dan Evans or American Marcos Giron in the quarter-finals.

France’s Jeremy Chardy also made the last eight, easing past American Taylor Fritz 6-2, 6-4.

On a day when players face playing two matches, after Thursday’s schedule was suspended over a coronavirus case, Italian teenager Jannik Sinner beat Slovenia’s Aljaz Bedene 7-6 (7/6), 6-2.

Sinner, who in November became the youngest ATP champion in 12 years when he won in Sofia, hit nine aces in his impressive victory to reach the quarter-finals of the Great Ocean Road Open.

But Spaniard Carlos Alcaraz, who upset top seed David Goffin in the second round, went down 7-6 (7/3) to Brazilian Thiago Monteiro.

Second seed Karen Khachanov joined them in the last eight, overcoming former world number five Kevin Anderson in straight sets.

He will play Botic Van de Zandschulp for a spot in the semis after the Dutchman upset big-serving American Reilly Opelka, the sixth seed.