ATK's David Williams scored the all-important goal in the 48th minute to seal the win on a day when Chennaiyin FC did everything but score.
Nerijust Valskis struck twice as Chennaiyin FC hammered Jamshedpur FC 4-1 in an Indian Super League match in Chennai on Thursday to boost its chances of making it to the play-offs.
It was Chennaiyin FC's first win in 289 days, bringing a lot of relief for Gregory, who two weeks ago was contemplating an exit.
Goian's 83rd-minute strike was enough for Chennaiyin to win the contest 1-0 and complete the ISL play-off lineup.
ATK may have qualified for the play-offs, but the loss came as a big blow to their AFC Champions League qualifying aspirations with FC Goa taking a three-point lead at the top with only a match left for the league stage to conclude.
On a night of missed opportunities, the two-time champions rode on goals from Rafael Crivellaro and Nerijus Valskis in the 57th and 59th minutes respectively to pocket three points, which takes it to sixth in the points table with 15 points.
A rampaging ATK claimed an unprecedented third Indian Super League title triumph with a 3-1 victory over arch-rival Chennaiyin FC in a summit showdown that was played behind closed doors in Margao on Saturday. Javier Hernandez (10th minute) and Edu Garcia (48th) put ATK in the driving seat but Nerijus Valskis (69th) reduced their advantage to set up a tense end to the contest. Hernandez scored another in injury time (90+4th) to confirm a record third title.
Real Kashmir scored their first victory of the ongoing I League season with a 2-1 defeat of the defending champion Chennai City.
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