TOKYO -- Kei Nishikori had an emotional farewell to his tennis career at the Japan Open.
Nishikori lost 6-4, 6-4 to second-seeded Frances Tiafoe in the first round Thursday. The 36-year-old Nishikori, a former US Open finalist with a career-high ranking of No. 4, said earlier in the week that he had mixed feelings about playing in his last elite-level tournament on home soil.
"I am excited to play in Japan, but I also know this is my last moment," he said. "So it's kind of sad."
Nishikori announced in May that he planned to retire at the end of the year and was granted a wild-card entry to the Japan Open, which he won in 2012 and 2014. His career ended with the loss.
He missed the Australian Open in January with right shoulder pain and has been affected by injuries the past several years. He also missed last year's US Open.
Making his professional debut in 2007, Nishikori became the first Japanese player to advance to the final of a Grand Slam men's singles tournament when he reached the championship decider at the 2014 US Open in New York, which he lost in straight sets to Marin Cilic.
In an earlier match Thursday in Tokyo, third-seeded Taylor Fritz lost 6-7 (7), 6-4, 6-3 to Spain's Jaume Munar.
Top-seeded Carlos Alcaraz was scheduled to play American Alex Michelsen later in the day. Last week, Alcaraz defeated Fritz 6-3, 4-6, 13-11 at the Laver Cup in London.
