But, Rohit Sharma silenced all his critics by producing a maiden half-century to end CSK's winning streak of five games at home this season.
Apart from Rohit, it was all-round effort that powered Mumbai to a much-needed 46-run win over defending champions at Chepauk on Friday.
Hardik Pandya took to Twitter and wrote it was time for "Hitman" to join the Avengers.
Rohit top-scored with 67 from 48 balls with the help of six fours and three sixes to help MI post 155 for four on a slow and turning Chepauk surface after being sent into bat.
Losing captain and CSK stand-in skipper Suresh Raina blamed the team's batting department for the loss.
"We didn't bat well. We kept losing wickets every 2-3 overs, so our batsmen need to take more responsibility. Our bowling has always been good this season. We thought 155 was chaseable. But we lost too many wickets in the powerplay and middle overs," he said.