Serena Williams’ doubles campaign at the Queen’s Club in London is thrown into uncertainty after her partner Victoria Mboko sustains a knee injury during her singles match. Multiple reports say Mboko, 19, suffers the injury in a match against Karolína Plíšková (also reported as Karolina Pliskova). The Athletic and BBC state that Mboko slips and injures her left knee, leading her to retire from the singles encounter. Sky Sports and The Guardian similarly report that Mboko is forced to retire after the knee problem develops in the course of play. Williams, 44, is reported to be in London for her return to tennis and recently played her first doubles match with Mboko, which resulted in a win. Because Mboko’s injury prevents her from continuing in singles, her ability to play the next scheduled doubles match with Williams is now in question, with reports noting that the duo were due to play on Thursday evening. The sources agree on the injury, the opponent, and the resulting doubt over the Williams–Mboko partnership at the tournament.