CFC had lost to ATK 1-2 in the away game and will be eager to get back to level terms.
Chennaiyin have faltered this season after winning the title in 2017-18 and John Gregory's attempts to find the right formula has been in vain. The usually reliable defence has been a letdown while the forwardline has been strangely off-colour.
ATK are better placed than Chennaiyin, at sixth place with 12 points, and would love to pick up maximum points to improve their position in the qualification race.
Coach Steve Coppell will want his men to exploit Chennaiyin's failings and score a win, which would put ATK in the top four.
SQUAD -- Chennaiyin and Kerala Blasters played out a goalless draw on Thursday at the Nehru stadium with both teams missing opportunities. The Blues will be hoping for course correction and some luck when they take on the ATK.
Raphael Augusto, who created a handful of opportunities against the Blasters, will be the key player again while the CFC fans will hope Jeje Lalpheklua regains his scoring touch. Gregory will be betting on Thoi Singh, Issac Vanmalswama and Anirudh Thapa to step up.
The three Chennaiyin forwards, Jeje Lalpekhlua, Carlos Salom and Mohammed Rafi, have scored just one goal between themselves this season. Even Chennaiyin's defenders have had better luck in front of the opposition goal than their forwards, with three goals and an assist.
ATK's biggest worry has been in their attacking players, who have failed to deliver the goals. The team has only managed to find the net on seven occasions in their nine matches so far, the joint-lowest tally this season alongside Mumbai City FC. To be fair, the Kolkata-based side have had their fair share of setbacks owing to injuries. The team lost star striker Kalu Uche to a muscle injury earlier this season and his replacement Emiliano Alfaro was sidelined with an Achilles injury without even playing a single minute. Everton Santos and Balwant Singh have had very little joy going forward, while new signing Eli Babalj only has 28 minutes of Hero ISL football under his belt. Captain Manuel Lanzarote has been the most influential player for ATK in the opposition third, but even he has looked a mere shadow of his former self.
A big boost for Coppell going into the match against Chennaiyin will be the upturn in the form of his defence. After failing to register a single clean sheet in their first six matches, the ATK defence stepped up in the last three outings and haven't conceded a single goal. The ploy to bring in Andre Bikey as John Johnson's centre-back partner and deploying Gerson Vieira as a defensive midfielder has paid off for Coppell. Vieira will, however, be without his midfield partner Pronay Halder on Sunday owing to a suspension.
FORM -- It has been a hard season for the defending champions who have just one win and two draws from nine games for five points, and cannot afford any further slip-ups as the race for the qualification gets tougher.
Head coach John Gregory, who marshalled the resources wonderfully well last year has tried various combinations but not found the right one.
Despite retaining the core of their title-winning side from last season, Chennaiyin have struggled this time around and the team has looked disjointed at times. With any realistic chances of a top-four finish slipping away fast, it will be interesting to see if Chenaiyin can get their act together and mount a late charge. But it needs to start on Sunday against ATK, or else it just maybe a little too late for the Marina Machans to salvage anything from the season.
Chennai have scored 10 goals from 39 shots on target. They have the passing accuracy of 72.89 per cent and have kept two cleansheets.
ATK are coming off two draws (against FC Goa and Mumbai City) and will look to return to winning ways. The forwards will need to get going and with the Chennaiyin FC defence not at its best, this could be the opportunity.
This season, Steve Coppell's ATK have been mediocre at best and have scored seven goals from 31 shots on target. They have the passing accuracy of 62.14 per cent and kept three cleansheets.
CHENNAIYIN FC: Karanjit Singh (GK), Inigo Calderon, Eli Sabia, Mailson Alves (C), Jerry Lalrinzuala, Anirudh Thapa, Germanpreet Singh, Francisco Fernandes, Raphael Augusto, Gregory Nelson, Jeje Lalpekhlua
ATK: Arindam Bhattacharja (GK), Ankit Mukherjee, John Johnson, Andre Bikey, Ricky Lallawmawma, Gerson Vieira, Hitesh Sharma, Komal Thatal, Manuel Lanzarote, Everton Santos, Balwant Singh