Alexander Zverev recognised his game remains below expectations after ending a six-month competitive absence, but the German is unconcerned as he continues his recovery.
The two-time ATP Finals winner suffered a serious ankle injury during the semi-finals of the French Open against Rafael Nadal, ruling him out of the rest of the 2022 season.
Though he has played in a number of exhibition matches since, Zverev only made his competitive return to action on Saturday at the United Cup in Sydney.
There, he suffered a 6-4 6-2 straight sets loss to the Czech Republic's Jiri Lehecka, though he was philosophical about his performance afterward.
"My tennis is far away from the level I want it to be," he said. "I think it is normal, not playing for seven months. There are things that are different than I'm used to.
"[Am I] concerned? Probably not. Physically, I'm not at the level that I have to be. This is not even a question. I'm getting tired a lot quicker than I did. I'm not as fast as I probably was.
"I don't think it will be a matter of tomorrow, [or] after tomorrow. It will be a few weeks until I'm back to the level I want to be."
Zverev, an Olympic gold medallist and US Open finalist, is anticipated to figure in next month's Australian Open, where he will be chasing a maiden grand slam trophy.
The German is focused on reaching full fitness rather than putting undue pressure on himself, though, adding: "I think it's tough to set expectations right now.
"It would be unrealistic and quite stupid for me to set the expectations towards winning or something like that.
"Of course, I want to win. Everybody wants to win. [But] for me, it's about getting back the form that I'm used to."