SERENA WILLIAMS’S Wimbledon appearance in women’s doubles with sister Venus is in doubt because of a knee injury.

The 44-year-old made her return in singles after nearly four years away on Tuesday night to a rapturous Centre Court reception.

Williams produced a strong display before fading in a 6-3 6-7 (6) 6-3 loss to 20-year-old Australian Maya Joint.

There had been no indication during the match that the 23-time grand slam singles champion had hurt herself but she did not attend the customary post-match press conference, instead issuing a short quote.

Players can be fined for skipping press conferences but it was revealed today that Williams was physically hampered.

A statement from the American’s agent Jill Smoller read: “Serena tweaked her right knee at the end of the first set and was therefore excused from her media obligations by the Wimbledon and WTA medical teams.

“She left site that night unaided and is doing everything she can to be ready for her doubles match later this week.”

Williams later added on Instagram: “It felt so good to be back on the grass at @wimbledon. I’m incredibly thankful for the wild card — and even more grateful my daughters got to see that it’s never too late to chase something you love.

“I tweaked my knee late in the first set, but I’ll be doing everything I can to be ready for doubles with @venuswilliams.

“Congratulations to @maya.joint on a great match, and thank you to everyone who showed up and showed me so much love. That feeling will never get old.”

Serena and Venus have taken a wild card into the doubles for their first appearance together at the All England Club since they won their sixth title a decade ago.

Serena had admitted ahead of the tournament that she remained unsure whether playing in singles was a good idea but concluded it was an opportunity she could not turn down.

She could not have asked for better support from the crowd and the competitive juices were certainly still flowing as she saved a match point in the second set.

Serena won seven grand slam singles titles before Joint was born, and the Australian admitted she was unable to sleep thinking about the occasion.

She was impressed by Williams’s level, saying: “I really didn’t know what to expect.

“I went in thinking that she’d bring her best game that she brought when she was at her peak, because you need to prepare for the hardest possible match. I think she played really well.”

Four-time grand slam champion Naomi Osaka enjoyed Williams’s return but had to go to bed before the deciding set to be ready for her second-round match against Anastasia Gasanova this morning.

“The montages that they had before the match started made me really emotional because I feel like I’ve watched her growing up,” said Osaka, who beat Gasanova 6-3 6-2.

“Now I feel like I’m grown up and I get the privilege of watching her again, so it was really cool.”