Thanasi Kokkinakis isn't sure how long it'll take for him to be back - but is adamant he will be.
Fresh from his maiden senior title win in the doubles at the Brisbane International, the forgotten talent of Australian tennis will make his long-awaited singles comeback in Sydney on Tuesday.
It's been an agonising 15-month wait for his return to the tour, but Kokkinakis has no idea how patient he'll still have to be to return to the kind of form that thrust him into the top 70 in 2015.
That was when he went toe-to-toe with Novak Djokovic at Roland Garros, and took then-world No.12 Richard Gasquet to five sets at Flushing Meadows.
It was an impressive level of play that he admits fuelled his comeback throughout major shoulder, pectoral and, more recently, groin injuries.
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"I know I have reached it in practice already. Last couple of weeks, I feel like I have been practising good," he said at the Sydney Olympic Park Tennis Centre on Monday.
"But practice and matches is so different with the intensity of everything, trying to sustain that level under a lot more pressure... I know my level is there.
"So it's about me staying healthy, feeling good, and being able to produce it when it matters."
The 20-year-old begins his long climb against doubles partner Jordan Thompson, just two days after the pair lifted their first tour silverware in Brisbane.
The duo caught the same plane and car to Homebush.
"It happens. You're all in the draw, and because we are not seeded we've obviously got the potential to draw each other. I don't know have high expectations," he said.
"I know what my level is capable of, but the biggest thing for me, and it's going to continue to be this same goal for the next years of my tennis, is just to stay as healthy as possible."
Fellow Australian Matthew Barton became the first local into the second round on day two by claiming arguably the biggest scalp of his career, edging world No.45 Kyle Edmund.
Ranked 153 places below the Great Britain No.2, Barton went game for game with Edmund for the entire match but earned his 7-6 (7-3) 7-6 (7-5) win with timely points in both tiebreakers.
He will now face either Gilles Muller or Alexandr Dolgopolov in the second round.
A second Australian qualifier in Christopher O'Connell wasn't so lucky, going down 7-6 (7-3) 6-4 6-1 to Gastao Elias, while Daniel Evans topped Thiago Monteiro 6-3 4-6 6-3.
Fifth-seed Phillip Kohlschreiber made a strong start to his campaign with a 6-4 6-4 win over Fabio Fognini, and Florian Mayer outlasted Paolo Lorenzi 7-6 (7-4) 4-6 7-6 (7-5) epic.
