Alex de Minaur has opened up about the despair of being in isolation and hopes the "dark" days of 2020 will drive him to new levels in 2021.
De Minaur has already made a lightning start to the new season, landing the fourth ATP title of his career in Turkey.
The Australian No.1's perfect start to the year came after he gatecrashed the quarter-finals of a grand slam for the first time last September in New York.
But the 21-year-old says his run to the US Open last eight couldn't make up for the torture of being in lockdown alone at his Spanish base for months on end as coronavirus wrought havoc.
"2020 was a tough year. Obviously I had my best result at a slam but it doesn't feel like my best achievement," de Minaur told AAP when asked why last year was such a wrench.
"It was still a dark time. I wasn't feeling great. It was just mentally, I wouldn't say my best performance.
"I ended up putting a couple of matches together and I had my best result. It's still something to be proud of but still 2020 as a whole, I would say I had a lot of expectations for it and ... look, it's just fuelling the hunger for 2021, to make it even better."
De Minaur has one more week in quarantine in Melbourne - able to leave his hotel room only to train - and can't wait to get his "freedom back".
"I'm sure that will feel amazing," he said, eyeing a further climb up the rankings from No.23 in the world.
"I've got my goal in my head of where I want to be when 2021 finishes up, but it's a goal that I don't like to say out loud.
"It's a goal that me and my team had and this is a strong start. Realistically I want to keep pushing myself up the rankings, keep putting myself at the end of weeks and keep pushing these top guys.
"That's where I believe I should be and where I want to be and I'll do everything I can to get there."
The second-youngest player in the top 25 says he spent much of the extended pre-season working on his body and mind.
"Working to take it to the top guys, to be able to push these top guys," he said.
"So that means hitting the ball a bit bigger, being a bit more aggressive, getting a bit stronger - these things - until it becomes just natural.
"I don't want just to be having a good result every now and then. I want to be bringing my level every single week."
De Minaur missed last year's Australian Open with an abdominal tear, an injury he picked up while leading Australia to the ATP Cup semi-finals.
He will again spearhead Lleyton Hewitt's line-up next week in Melbourne before returning for another tilt at his home slam.
"Hopefully I can be playing my best tennis at the ATP Cup and the Aussie Open," de Minaur said.
Australian Associated Press