Martin Andrew Paterson(19) of ATK jubiliate after score a goal against Chennaiyin FC during ISL Match in Kolkata on Thursday.Pic/PTI

Chennaiyin FC came from a goal down to beat two-time champions ATK 2-1 in an Indian Super League match and jump to top of the standings, here today. A change of guard did see ATK gain the upperhand as the defending champions, under interim coach Ashley Westwood, drew the first blood through new signing Martin Paterson in the 44th minute.