The 29-year-old showed his disappointment with the umpire's leg before wicket decision off Sunil Narine's bowling and expressed his anger while walking back to the pavillion at the Wankhede Stadium here last night.
Although Mumbai Indians won the match by four wickets, at the time when Rohit got out the team needed 105 more runs off 62 balls.
"Rohit Sharma, the Mumbai Indians captain, was reprimanded by the match referee for showing excessive, obvious disappointment with an umpire's decision during his team's contest against the Kolkata Knight Riders at the Wankhede Stadium," an Indian Premier League (IPL) statement said.