Kei Nishikori in action Thursday at the Atlanta Open.

Kei Nishikori takes the court in Atlanta for his first tour-level match since October 2021.

Kei Nishikori claws past Jordan Thompson in Atlanta on Tuesday in two tie-breaks.

Kei Nishikori breaks Joao Sousa's serve seven times on Thursday to advance to the second round in Indian Wells.

Kei Nishikori defeats Miomir Kecmanovic on Tuesday in Toronto.

Kei Nishikori defeats Miomir Kecmanovic on Tuesday in Toronto.

Kei Nishikori breaks three times on his way past Sam Querrey in the opening round in Washington.

Ben McLachlan and Kei Nishikori defeat British pair Jamie Muray and Neal Skupski on Monday in Tokyo.

Kei Nishikori defeats Alexei Popyrin at Wimbledon to record his 100th Grand Slam win.

Kei Nishikori improves to 26-7 in five-set matches after he beat Karen Khachanov on Wednesday at Roland Garros.

Kei Nishikori improves to 25-7 in five-setters with his victory against Alessandro Giannessi on Sunday in Paris.

Kei Nishikori, the 2014 finalist, beats Karen Khachanov on Tuesday in Madrid.

Kei Nishikori, the 2014 finalist, beats Karen Khachanov on Tuesday in Madrid.

Kei Nishikori owns a 23-6 record at the Barcelona Open Banc Sabadell.

Kei Nishikori is enjoying the challenge of returning to his best level after three years of injury woes.

Kei Nishikori lost to Pierre-Hugues Herbert on Tuesday in the Marseille first round.

Kei Nishikori beats last year's finalist Felix Auger-Aliassime on Monday in Rotterdam.

Team Japan captain Max Mirnyi has been a part of Kei Nishikori's coaching team since December 2019.

Kei Nishikori struck 41 winners in his five-set win against Daniel Evans at Roland Garros.

Kei Nishikori battles past Daniel Evans on Sunday for a place in the Roland Garros second round.

Kei Nishikori is a three-time Roland Garros quarter-finalist.

Daniel Evans, the No. 32 seed, congratulates Kei Nishikori on his first-round victory on Sunday at Roland Garros.

Kei Nishikori will battle clay-court stalwart Cristian Garin in his Hamburg opener.

Kei Nishikori has never lost his opening match at the Internazionali BNL d'Italia.

Kei Nishikori, playing his first tour-level event since August 2019, battles hard on Tuesday against Miomir Kecmanovic.