Rohit Sharma's team have won the IPL a record five times but this year have failed to come anywhere near their best, suffering eight successive defeats.
A combination of poor form of top order batsmen Sharma and Ishan Kishan, combined with a lack of threat in the bowling department - apart from Jasprit Bumrah - has almost certainly ended Mumbai's hopes of qualification for the play-offs.
The danger signs were there during the player auction earlier in the year when Mumbai spent a record 152.5 million rupees ($2.02m) on Ishan Kishan and did not invest on a well-rounded bowling attack - instead spending $1m on an unfit Jofra Archer with an eye on 2023.
It was another disappointing, albeit expected, result for Mumbai on Sunday when they failed to chase down 169 against Lucknow Super Giants, stumbling to 132-8 after three of their top four batsmen got out for single digit scores.
After the defeat, captain Sharma said poor batting has hurt his team the most.
"When you have a target like that, it is very crucial to string those partnerships," Rohit told broadcaster Star Sports. "We didn't do that, and then a few irresponsible shots including from myself. We couldn't get the momentum when we needed.
"We haven't batted well enough in this tournament. The whole thing goes on the batting unit. Whoever plays in the middle needs to take that responsibility and make sure one of the batters bats long. We've failed to do that."
However, Mumbai can take some consolation in the fact that this is not the worst run of defeats in franchise cricket, even though they became the first team in IPL to lose their first eight matches. In the picture gallery above, you can find the list of teams with the worst losing streaks in T20 franchise cricket.