Miomir Kecmanović — who was scheduled to play Novak Djokovic in the Australian Open first round — says he is making the most of what he describes as a "second chance" following the withdrawal of his fellow Serb.
Kecmanović was speaking on Friday after he reached the fourth round of a major for the first time, having defeated Italian 25th seed Lorenzo Sonego 6-4, 6-7 (8-10), 6-2, 7-5.
He will play Gael Monfils in the last 16 after the 17th-seeded Frenchman won his third-round match against Chile's 16th seed Cristian Garin 7-6 (7-4), 6-1, 6-3.
Kecmanović's progression to the last 16 has benefited from Djokovic's absence from the Australian Open.
The men's world number one was deported from Australia last Sunday night after the Federal Court upheld a decision by Immigration Minister Alex Hawke to cancel his visa.
His place in the main draw was taken by Italian "lucky loser" Salvatore Caruso, who lost to Kecmanović in the first round.
Kecmanović then defeated American Tommy Paul in his second match.
The world number 77 acknowledged he was taking advantage of Djokovic not being in the tournament, as the 22-year-old had been at long odds to beat the nine-time champion.
He said he was determined to make the most of the opportunity.
"It's unbelievable," Kecmanović said.
"But now I'm in the last 16, so I'm happy that I was able to use this chance and that I've been playing some really good tennis."
Kecmanović said Djokovic's withdrawal had changed his mindset at the tournament.
"I didn't have much pressure, just because I felt that I got a second chance, so I just wanted to use it the best that I can," he said.
"I've obviously been showing that well up until now."
Kecmanović said he had not been in contact with Djokovic since his countryman had arrived back in Serbia earlier this week.
"I think he's still recovering from everything, and I didn't really want to bother him, [I want to] give him his space," he said.
"I'll definitely talk to him eventually after things calm down."