Began playing tennis at age 5 Shares a son with wife, Mai Mother, Eri; father, Kiyoshi; sister, Reina Left Japan at age 14 to train at IMG Academy in Bradenton, FL, USA. Didn't speak a word of English when he arrived. Still trains at IMG Academy Travelled to USA as a member of Masaaki Morita Tennis Fund group, which consists of a select group of Japanese players sponsored by Mr. Akio Morita, CEO of Sony Download his phone app at keisapp.com Favourite shot is forehand and favourite surfaces are hard and clay Named 2008 ATP Newcomer of the Year In 2011, played current coach Michael Chang in Tokyo to raise money for earthquake relief During COVID-19 pandemic, teamed with DJ Steve Aoki and finished 2nd in a Nintendo Mario Tennis tournament. Donated $25,000 to charity Underwent right elbow surgeriesin August 2009 and October 2019, as well as hip surgery in January 2022

Top Asian men’s player in history, achieving career-high No. 4 in 2015

Earned biggest of 433 career wins over No. 1 Djokovic at 2014 US Open to become 1st Asian Grand Slam men's singles finalist

Captured 1st of 12 ATP Tour titles at 2008 Delray Beach as 18-year-old Q ranked 244th and remains youngest champion on tour since Hewitt, 16, at 1998 Adelaide

Six-time ATP 500 champion, four-time ATP Masters 1000 finalist, four-time Nitto ATP Finals qualifier and 2016 Rio Olympics bronze medallist

Owns highest winning percentage among active players in 5-set matches, winning 12 of last 13 (27-7, .794) and highest in deciding sets (147-56, .724), just ahead of Djokovic (213-83, .720)

Underwent hip surgery in February 2022 and was out for the entire season. Then injured his ankle in late 2022 while practicing and delayed his comeback for another 4-5 months

Returned at 2023 Palmas del Mar CH and became the first unranked player to win a Challenger title