Roger Federer had been away from the ATP Tour for so long that he appeared forgot the rules on Wednesday.
The Swiss legend marked his eagerly-awaited return to action after more than a year with some vintage tennis as he beat Dan Evans 7-6 (10-8) 3-6 7-5 at the Qatar Open.
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The 39-year-old hadn't played a competitive match for 405 days and underwent two knee surgeries in 2020, but it was if he had never been away as he clicked smoothly back into gear against the British No.1.
However it wasn't all smooth sailing, with Federer admitting after the match that he didn't know all the new rules.
Federer joked at the coin toss that he didn't know the rules of the sport during the COVID-19 pandemic, having not played since the ATP Tour was suspended last year due to the pandemic.
"I tend to forget a lot of things... like I'd ask for the towel and they couldn't bring it to me because of the (coronavirus) rules," he said after the game.
"It feels like I've been away longer than I have."
Federer said he "couldn't care less about the outcome" despite the win.
"It felt great to be out there again... it will give me a lot of answers," he said.
"It's going to be interesting to see how I feel tomorrow," he added following his epic two hours and 24 minutes victory.
"I was very happy with how I was able to handle the tough moments, I didn't think my game started to wobble."
Roger Federer makes sparkling return to ATP Tour
A socially-distanced evening audience at the Khalifa Tennis Complex was treated to a high-quality duel, with Evans pushing the 20-times grand slam champion to the limit.
Federer showed great physical condition and kept his nose in front in the deciding set before pouncing in the 12th game to rifle a backhand winner down the line on his second match point.
It was a magical moment for Federer, who said it had been a long and tough road since his last match - a semi-final defeat by Novak Djokovic at the 2020 Australian Open.
"It feels good to be back, happy to be standing here whether I won or lost," the evergreen Federer, who received a bye in the first round, said on court.
"I was tired and focused on being tired rather than winning the points. If I was going to go out I wanted to go out swinging.
"Incredibly happy about my performance and it was nice to finish with a backhand winner down the line."
Federer and Evans had played around 20 practice sets in the build-up to the tournament, but the real test was how the Swiss would hold up in real match conditions.
The answer was emphatic.
From the first point, he struck the ball with his trademark panache and power and his serve was ruthlessly efficient.
Evans, 30, said after the match: "It was clear he'd been off but (he) showed a lot of glimpses of why he's so good".
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