Things got worse for Kerala in the 45th minute when Valskis combined beautifully with Crivellaro before receiving the return pass and lashed a finish home. A minute later, Kerala were caught napping again.
Anirudh Thapa sent a through ball forward for Valskis who was offside. But the Lithuanian did not interfere with play and Crivellaro took advantage, surged towards goal and finished with aplomb to make it 3-0 in no time.
The setbacks sparked a reaction from Kerala in the second half with Ogbeche leading them. Three minutes into the half, the Nigerian got on the end of a hopeful cross into the box from Jessel Carneiro and turned it in past goalkeeper Vishal Kaith.
However, Chennaiyin restored their advantage after yet another howler from the Kerala defence. Abdul Hakku's intended pass for Rehenesh was intercepted by Valskis who set up Chhangte who arrowed it past the Kerala goalkeeper.
Ogbeche had other ideas and scored a quickfire brace to make it 4-3.
In the 65th minute, he beat Kaith with a clinical shot from outside the box before heading in Halicharan Narzary's cross in the 76th minute.
When one thought Chennaiyin had lost the plot, Chhangte settled their nerves with a fine strike from range in the 80th minute.
After that Valskis helped himself to a second goal late on to seal a goal glut.