Despite missing out on the ATP Comeback Player of the Year Award, ninth-ranked Kei Nishikori said he is happy with the way his season unfolded, especially after he became one of eight players to qualify for the year-end finals.

Nishikori will face former world No. 1 Roger Federer Sunday at London's O2 Arena, a challenge that comes at the end of a long road that included finishing a five-month wrist injury layoff in January and then starting his 2018 campaign on the second-tier Challenger circuit.

"I'm really happy. It's not easy to come here. I'm going to compete thinking I've been given a bonus," said Nishikori, who had a one-hour training session with fifth-ranked German Alexander Zverev before the press conference.

"It's tough to have to face Federer in the opening match, but I hope to give it my all. I'll play with confidence," he said.

The 28-year-old Japanese will make his fourth ATP Finals appearance and first since 2016. He reached the semifinals twice, in 2014 and 2016, and was beaten by Novak Djokovic both times.

Nishikori has been drawn into "Group Lleyton Hewitt" alongside Federer, Kevin Anderson and Dominic Thiem. Djokovic, Zverev, Marin Cilic and John Isner are in the other pool, "Group Guga Kuerten."

Djokovic, who underwent elbow surgery in February and ended the year as world No. 1, received the Comeback Player of the Year award on Friday. If the Serb can win his first ATP Finals title since 2015, he will equal Federer's record of six crowns.

The Nov. 11-18 event, which features the top eight singles players and doubles teams in the ATP rankings, has a round-robin format. The top two in each group progress to the knockout semifinals.