Serena Williams’ eagerly anticipated Wimbledon doubles reunion with sister Venus has been thrown into doubt after she injured her right knee during her singles comeback.The 44-year-old’s representative confirmed to the Daily Mail on Wednesday that Williams ‘tweaked’ her knee during her first-round defeat to Australia’s Maya Joint, explaining why she was excused from her mandatory post-match media duties.The update raises fresh uncertainty over whether Serena will be fit to take to the court alongside Venus later this week, with the sisters due to make their long-awaited return as a doubles partnership at the All England Club.Williams herself shared that she was doing ‘everything’ to ensure she can return to court, posting a statement on social media on Wednesday afternoon. ‘It felt so good to be back on the grass at Wimbledon,’ Williams wrote on Instagram. ‘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 Venus. 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 Williams’ team have hit back at ‘astounding’ criticism of the 44-year-old tennis star Williams elected to skip her mandatory press conference after her match on Tuesday nightJill Smoller, Williams’ agent said: ‘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.’While Smoller’s statement stressed that Williams is working to recover in time, it stopped short of guaranteeing she will be available, leaving a cloud hanging over one of the most anticipated storylines of this year’s Championships. Serena is due to team up with Venus on Friday in the first round of the doubles, an event the sisters have won together six times. The Williams’ will play Argentine/Colombian pair Solana Sierra and Camila Osorio – if Serena is fit to take to the court.Between them, Serena and Venus have won 14 Grand Slam doubles titles and three Olympic gold medals, with Wimbledon holding particular significance after the pair lifted the ladies’ doubles trophy six times together. Williams had returned to Centre Court on Tuesday night for her first Wimbledon singles match since 2022 and her first Grand Slam singles appearance in almost four years.For almost two and a half hours, Centre Court dared to dream there was one more Serena fairytale left to be written.Roared on by a standing ovation as she emerged onto the famous court and backed by a packed 15,000-strong crowd throughout, the seven-time Wimbledon champion rolled back the years with flashes of the power and determination that defined her career.She battled back from a set down, saving match point in the second-set tie-break before forcing a deciding set, only for 20-year-old Australian Maya Joint to eventually prevail 6-3, 6-7 (6), 6-3.Although much of Williams’ trademark power remained, her movement looked increasingly restricted as the contest wore on and this knee issue could explain why.As the media waited for Serena to appear on Tuesday night, an alert came through from the All England Club, saying: ‘Unfortunately Serena Williams will not be able to undertake media this evening. Please see below quotes from her: “It was really great to be back at Wimbledon. I never expected to be here. The atmosphere was amazing. Walking out was amazing. I definitely relished it and missed it and enjoyed the moment more than anything.”‘This set off a storm of social media criticism, with fans attacking Williams for skipping press, implying effectively that she had flounced off after a tough defeat.But the wording of the announcement that Williams would be ‘not able’ to do media suggested something more concrete than a mere refusal. On Wednesday morning the All England Club confirmed to Daily Mail Sport that Serena would not face the usual fine of up to £37,000 for skipping media duties, which again implied there was a legitimate reason.One of Serena’s coaches, former doubles world No1 Rennae Stubbs, hit back at the social media critics, posting: ‘The hate and lack of empathy in this world is astounding to me. Especially when you have no idea what you’re talking about. Just blows my mind.’