Why Dhoni promoted Jadeja and Curran ahead of him ?Know the reason

Mahendra Singh Dhoni returned to the cricket field on Sunday after 437 days. Fans were hoping that after a long time, Dhoni will come to the field, then he will get a big knock with his bat. But this did not happen. Captain Dhoni came for batting but in the final moments.  Chennai Super Kings needed only 10 more runs to win.

Why did captain Dhoni promote Ravindra Jadeja and Sam Curran in the batting order? Captain Dhoni says that there was a psychological reason behind this. He wanted both of them to go there and put pressure on Mumbai with a couple of sixes. He also wanted Jadeja and Curran to express themselves.