Pavel Šnobel was the defender of title; however, he lost to Evgeny Kirillov in the first round.
Lukáš Lacko became the new champion, after he beat Samuel Groth in the final.
Benedikt Dorsch was the defending champion, but he chose to not start this year.
Mikhail Kukushkin defeated Illya Marchenko 6–4, 6–2 in the final.
Rubén Ramírez Hidalgo was the defending champion; however, he was eliminated already in the first round by Ivo Klec.
Arnau Brugués-Davi was the defending champion but decided not to participate.
Illya Marchenko won the tournament by defeating Evgeny Donskoy 7–5, 6–3 in the final.
Tobias Kamke was the defending champion but was defeated by Evgeny Donskoy in the semifinals.
Donskoy won the title by defeating Jan-Lennard Struff 6–2, 4–6, 6–1 in the final.
Philipp Kohlschreiber was the defending champion but lost in the final to Tommy Haas, 3–6, 6–7(3–7).
Juan Mónaco won the first edition of the tournament, defeating Jarkko Nieminen in the final, 6–4, 6–3
Evgeny Donskoy was the defending champion, but lost to Illya Marchenko in the quarterfinals.
Yuki Bhambri is the first winner of the event, defeating Alexander Kudryavtsev in the final 4–6, 6–3, 7–5.
This was the first edition of the event.
ONGC-GAIL Delhi Open is now known as Delhi Open. The first edition of this tournament was held in 2014. The category of Men's Singles of this tournament was won by Somdev Devvarman. He defeated Aleksandr Nedovyesov in the final, 6-3, 6-1. Though Aleksandr started playing the tournament being the number one seed. Yet, he had been defeated by the number 2 seed of the tournament.
Mikhail Kukushkin was the defending champion, but did not take part this year.
Stan Wawrinka was the defending champion, and successfully defended his title against Slovenian qualifier Aljaž Bedene, 6–3, 6–4.
Marin Čilić was the two-time defending champion, but withdrew before the tournament started due to an arm injury.
Marsel İlhan was the defending champion, but he lost in quarterfinals to Konstantin Kravchuk.
Mirza Bašić was the defending champion but chose not to participate.
Evgeny Donskoy was the defending champion but chose not to defend his title.
Nick Kyrgios was the defending champion, but lost in the semifinals to Jo-Wilfried Tsonga.
Lu Yen-hsun was the defending champion but chose not to defend his title.
