"It was always going to be hard for Corey to fire in his first IPL as Mumbai Indians paid a lot of money for him which added the pressure on him," Doull told PTI here in an interview.
"They are not the team they were last year so now there is more pressure on Cory to perform which is not how it should be for a young man still finding his way in the early part of his career," he said referring to the defending champions dismal run this season.
The management opted for the New Zealand all-rounder rather than retaining the likes of Glenn Maxwell and Dwayne Smith, who are doing well for their new teams -- Kings XI Punjab and Chennai Super Kings respectively.
"Look how Smith and Maxwell are doing now. Theirs are a good example of how a more relaxed atmosphere can help you perform better," said Doull, who is now a well-known commentator.