 Japanese wheelchair tennis player Shingo Kunieda said Sunday he has decided to hang up his racquet. The 38-year-old, who won Paralympic gold in the mens singles in Tokyo in 2021 and completed his career Grand Slam by winning Wimbledon last July, announced the decision on his Twitter account. Shingo Kunieda of Japan plays against Alfie ... Japanese wheelchair tennis player Shingo Kunieda retires... 