[6] Novak Djokovic began his season in Qatar ExxonMobil Open, where he reached the quarterfinals before losing to Ivo Karlović in a tight three set match.

After losing the final in Dubai Tennis Championships to Roger Federer, Djokovic went on a 28-match winning streak, first leading Serbia to the quarterfinals of the Davis Cup before winning the first three Masters 1000 titles of the year at the BNP Paribas Open, Miami Open and Monte-Carlo Rolex Masters, beating Federer, Murray and Tomáš Berdych respectively in the finals.

At the French Open, Djokovic once again made it to the final, defeating Murray en route in a gruelling 5-set thriller in the semi-finals.

Ultimately he lost the final to Stan Wawrinka, denying the Serb a first title in Paris and a Career Grand Slam.

Djokovic then ventured to the Shanghai Rolex Masters as a three-time champion he was once again victorious, defeating Jo Wilfried Tsonga in the final.

Murray withdrew prior to his third round match against David Goffin in Rome Masters, citing fatigue, before reaching his third semi-final at the French Open, losing again to Djokovic in a thrilling five-set encounter.

He couldn't carry the momentum into the Australian Open however, losing in the third round against Andreas Seppi, bringing to an end his record streak of 11 consecutive semi-final appearances in Melbourne.

After skipping the first round of the Davis Cup, Federer reached the final in Indian Wells for a record sixth time, however lost to Djokovic in three sets.

After an early exit in Monte-Carlo Rolex Masters against Gaël Monfils, Federer won the third title of his season, at the inaugural Istanbul Open, defeating Pablo Cuevas in the final.

During the grass court season, Federer won a record eighth title in Gerry Weber Open, defeating Seppi in the final.

Stan Wawrinka began the year by successfully defending his title at the Aircel Chennai Open against Aljaž Bedene.

Coming in as the defending champion at the Australian Open, he was unable to lift the title when he lost to Novak Djokovic in the semi-finals after losing the fifth set in a bagel.

At the US Open, Wawrinka continued his good form at the slams, when he reached the semi-finals but once again he lost to his compatriot Federer in three quick sets.

He won his fourth title of the year at the Rakuten Japan Open Tennis Championships defeating France's Benoît Paire in the final.

Back at Europe, Wawrinka suffered an upset loss at his home tournament Swiss Indoors losing to Ivo Karlović in the first round.

Rafael Nadal began the year as the defending Champion at the Qatar Total Open, but suffered a shocking three set defeat to Michael Berrer in the first round.

At the Australian Open, Nadal lost in straight sets to Tomáš Berdych in the quarterfinal, thus ending a 17-match winning streak against the seventh-seeded Czech.

Nadal then began his spring clay season at the Monte Carlo Rolex Masters and reached the semi-finals where he lost to Novak Djokovic in straight sets.

Nadal came into the French Open at the five time defending but lost to eventual runner-up Djokovic in the quarterfinals, ending his winning streak of 39 consecutive victories in Paris since his defeat by Robin Söderling in 2009.

Tomáš Berdych began the year by reaching the final of the Qatar ExxonMobil Open but lost the Spaniard David Ferrer in two tight sets.

Berdych then participated in the 2015 Monte-Carlo Rolex Masters, in which he defeated Gaël Monfils and Milos Raonic to reach the final, but eventually lost to Novak Djokovic.

Ferrer followed that up by winning back-to-back 500 event titles at the Rio Open and Abierto Mexicano Telcel by defeating Fabio Fognini and Kei Nishikori, respectively.

Kei Nishikori began the 2015 season by participating in the Brisbane International and reached the semi-finals before being beaten by Milos Raonic in 3 tight-set tiebreaks.

Nishikori equalled his best record yet in the Australian Open by reaching the quarterfinals, but he was beaten in straight sets by defending champion Stan Wawrinka.

Nishikori won his eighth singles title and became the first ever player to win the Memphis Open three times in a row, beating Kevin Anderson in straight sets in the final.

He next participated in the Abierto Mexicano Telcel losing to David Ferrer in straight sets in the final but reached a new career high world ranking of No.

Nishikori began his clay-court season at the Barcelona Open Banc Sabadell where he defended his title by beating Pablo Andújar in the final in two sets.

Nishikori became the first Japanese man to reach the quarterfinals of the French Open in 82 years but lost to home favorite Jo-Wilfried Tsonga in five set.

Nishikori decided to play Wimbledon, but withdrew from his second round match against Santiago Giraldo, due to his calf injury.

Nishikori started the Asian Fall by participating in his hometown tournament, Rakuten Japan Open, where he reached the semi-finals but lost again to Paire.