Right back - Mehrajuddin Wadoo
The 32-year-old was key for Chennaiyin FC in their title-winning campaign last season. The former Jammu and Kashmir policeman has played for Kolkata's big three clubs (Mohun Bagan, East Bengal and Mohammedan) and has gained lots of experience. The defending Champions will need aggressiveness and experience at the back this season and hence Wadoo will be keeping his spot in Chennaiyin's starting eleven.
Centre Back - Bernard Mendy
The former France, Paris Saint-Germain and Hull defender was Chennaiyin's first pick in the International draft of the Indian Super League in 2014 and the 35-year-old still remains as a key figure in Marco Materazzi's squad. Mendy, who has scored two goals and assisted one for Chennaiyin, was with East Bengal during the 2015-16 season of the I-League and now will be back with the Super Machans as their captain.
Centre Back - John Arne Riise
Chennaiyin FC's marquee player John Arne Riise will be partnering Bernard Mendy at the back. The former Liverpool man, who is actually a Left Back, played as a Centre Back for Delhi Dynamos and could do the same with Chennai to maintain the balance of the team. The Norwegian had returned to his homeland club Aalesund earlier this year, however, the former Roma player soon decided to take a break from football due to lack of motivation.
Chennaiyin FC was able to convince the 35-year-old to return to football for this season's Indian Super League.
Left Back - Dhanachandra Singh
The 26-year-old Manipuri defender is known for his versatility. The former Mohun Bagan player can play as a centre-back, defensive midfielder as well as a left back. However the Indian international is expected to occupy the left back position where he played for Chennai in the past two seasons of the tournament. The former Churchill Brothers player, who helped Mohun Bagan and Chennaiyin win League titles in 2015, will have to raise his performance levels to earn a constant spot in the Indian National Team.