*Signed with the Washington Spirit on December 18, 2019.
Prior to the Spirit: After graduating from high school, Yokoyama joined Okayama Yunogo Belle in 2012… In 2014, they moved to L.League Division 2 club AC Nagano Parceiro… Became top goal scorer in 2014 and 2015 as club was also promoted to Division 1 from 2016… In 2016 season… was selected to 2016 Best XI… In July 2017, they moved to German Bundesliga club Frankfurt… In July 2018, they returned to AC Nagano Parceiro. 2020: Started in all eight appearances in 2020… played a total of 578 minutes of game time… had one clearance and six interceptions… had a successful pass rate of 84-percent… Contributed eight key passes, nine crosses and four shots on target… Their lone goal of the season came against Sky Blue in the final game of the Fall Series for which they were awarded the 2020 Spirit Goal of the Year. 2021: Started 5 of 12 games… Played 293 minutes.
Selected to Japan U-17 national team for 2010 U-17 World Cup… Played 6 games and scored 6 goals, and Japan won 2nd place… Received one of ten 2010 FIFA Puskás Awards nominations for their winning goal in the semifinals against North Korea… In 2012 they were also a member of Japan U-20 national team for 2012 U-20 World Cup which Japan won 3rd place… Was selected by Japan for 2015 Algarve Cup… Debuted on March 6 and scored a goal against Portugal… In 2018, they played at 2018 Asian Cup… scored 4 goals including 2 goals in semifinal and a goal in final, and Japan won the championship.