Nick Kyrgios kisses his girlfriend Costen Hatzi at the Australian Open in Melbourne

Nick Kyrgios roared to victory on Saturday night, and his girlfriend Costen Hatzi was there, ready to congratulate him.

The Australian tennis champion won the men’s doubles final alongside Thanasi Kokkinakis against fellow Australians Matthew Ebden and Max Purcell at the Australian Open at Melbourne Park in Melbourne on Saturday night.

Costeen, 21, ran onto the pitch to hug Nick, 26, with the pair sharing a sweet kiss.

A clearly delighted Nick lifted his girlfriend up straight away as he embraced her, the pair beaming.

They then stopped for a quick selfie, with a smiling Costeen taking the image from her phone.

Kyrgios and Kokkinakis previously won a tense All-Australian Open men’s doubles final 7-5, 6-4.

The tight contest was ruined when an unruly fan was ejected from the stands at Melbourne Park’s Rod Laver Arena for disrupting play in the back-and-forth battle.

A pumped-up spectator at Melbourne Park’s Rod Laver Arena shouted “f*** off” at the end of the second set as a player served.

Kyrgios looked up at the bleachers and yelled at the security guards to “chase him away”.

Broadcast cameras showed the moment the embarrassed fan was approached by security personnel and handed the boot.

Nick went Instagram official with girlfriend Costen in December.

Costeen watched all of Nick’s games at Melbourne Park and was described as a key member of his team.