Alexander Zverev believes the Australian Open is already a success for him after his five-set victory against Juan Pablo Varillas on Tuesday.
It was the German's first win since his foot injury at the French Open in June during his semi-final against Rafael Nadal.
Zverev only returned to tour-level tennis in December at the United Cup, where he lost to Jiri Lehecka and Taylor Fritz.
He fell a set behind twice against the Peruvian lucky loser Varillas, before fighting back to win 4-6 6-1 5-7 7-6 (7-3) 6-4.
The world number 12 hit 69 winners and won 83 per cent of his first serve points in the contest, which lasted four hours and nine minutes.
"I am extremely happy because I missed this over the past seven months," Zverev said after his victory.
"This match alone pays off for all the hard work and suffering that I have had. To win in front of this kind of crowd again.
"I can't wait for the rest of the tournament. No matter what happens from now, the tournament is already a success for me."
Zverev will face the winner of Michael Mmoh or Laurent Lokoli in the second round, with their match suspended at two sets all on Tuesday due to rain.