The International Premier Tennis League (IPTL) has added a fifth team and re-signed several top players for its second season.

A team from Japan will join the original four Asian cities that comprised the first season. The teams conducted their drafts this week, with many players returning to play the off-season competition. Roger Federer, who was brought in to play when Rafael Nadal withdrew last year, committed from the very start this year to the UAE Royals. Nadal also signed up to play for his original team, the India Aces.

Leander Paes, who has had a tense relationship with his former doubles partner Mahesh Bhupathi, is also scheduled to play the Bhupathi-backed league for the Japan Warriors. Bhupathi said that Paes declined to participate the first year, choosing instead to play the Indian-based Champions Tennis League (CTS) started by Vijay Amritraj. Indian singles player Somdevv Devvarman has not been selected by any team.

Novak Djokovic, Serena Williams and Maria Sharapova are also returning to the IPTL. The league, which will be played for two-and-a-half weeks during the off-season, offers players significant money for competing. Nadal was said to been offered $1 million per match, and some other Top 10 and Top 20 players are getting that much for their participation in the entire competition. The teams consists of men's and women's singles and doubles players, with a retired legend serving as the captain.

The 2015 teams are as follows:

Indian Aces: Rafael Nadal, Sania Mirza, Rohan Bopanna, Gael Monfils, Fabrice Santoro, Agnieszka Radwanska

UAE Royals: Roger Federer, Ana Ivanovic, Tomas Berdych, Kristina Mladenovic, Marin Cilic, Daniel Nestor, Goran Ivanisevic

Manila Mavericks: Serena Williams, Jo-Wilfried Tsonga, Sabine Lisicki, Richard Gasquet, Mark Philippoussis, Jarmila Gajdosova, Borna Coric, Treat Huey

Singapore Slammers: Novak Djokovic, Nick Kyrgios, Karolina Pliskova, Carlos Moya, Belinda Bencic, Thanasi Kokkinakis, Marcelo Melo

Japan Warriors: Maria Sharapova, Kei Nishikori, Leander Paes, Vasek Pospisil, Marat Safin, Daniela Hantuchova, Lucas Pouille, Kurumi Nara