Former doubles World No. 1 Rennae Stubbs sympathized with Megan Rapinoe after the American soccer star's final career match ended with an injury.Rapinoe announced in July that she would retire at the end of the National Women's Soccer League (NWSL) season. In OL Reign's final match of the campaign against NJ/NY Gotham FC at Snapdragon Stadium, she suffered a non-contact injury to her right leg in the third minute.The 38-year-old limped off the field to a standing ovation from the 25,011-strong crowd and was replaced by Bethany Balcer.Stubbs, who coached Serena Williams in the final weeks of her career, took to social media to express her thoughts on a cruel end to Rapinoe's career."Absolutely SHATTERED for @mPinoe!!! SHATTERED!!!!! she doesn’t deserve to finish her incredible career like that," she posted.Rapinoe is a two-time World Cup winner and Olympic gold medalist with the USA. Incidentally, this match also brought the curtains down on former USWNT player and Gotham defender Ali Krieger's career. The two shared a warm hug when the former got substituted.Stubbs has been a longtime supporter of Rapinoe, who, besides being one of the legends of her sport, is also a vocal advocate for LGBTQIA+ rights, social justice, and equal pay.When Rapinoe played her last game for the USWNT at Soldier Field in Chicago on September 2, captaining the team to a 2-0 victory over South Africa, Stubbs took to social media to congratulate her Rapinoe on a stellar career."Congrats @mrapinoe on an amazing career & for always sticking up for equality!" she said on Instagram.Megan Rapinoe on Serena Williams: "She's a complete badass"Serena Williams is a 23-time Grand Slam champion.Despite playing in two different sports, Megan Rapinoe has always been vocal about her admiration for Serena Williams.When Williams vowed to continue her fight for equal pay, Rapinoe was quick to express her support. The soccer star vowed not to change her outspoken approach and follow in Williams' footsteps."You know what? I'm gonna fight for equal pay every day, for myself, for my team, and for every single person out there. Man, woman, immigrant, US citizen, person of colour, whatever it may be. 'Equal pay,' as the great Serena Williams said, 'til I'm in my grave'," she told NBC in 2019.Rapinoe also expressed her admiration for 'badass' Williams by stating that she thrived despite facing a lot of adversity and controversy."She's a complete badass. (Serena's) doing it all with such style, doing it in the face of so much adversity and controversy. She hasn’t really been allowed to be just Serena Williams, there's always something that comes with it," she told Shape Magazine."She handles and shoulders that so well and then just goes out there and is an absolute beast on the court. It's pretty cool to watch," she added.