The Ambanis may be having a big sigh of relief after watching yesterday's match. Their most expensive purchase (Cam Green) performed well against Sunrisers Hyderabad. But the other big purchases are yet to prove their worth. Rohit has so far had only one 30 plus score in 5 innings. Jasprit Bumrah is out injured. Ishan Kishan hasn't converted the starts he got to 50s. Tim David bats down the order, so I don't want to complain about him too much. But their biggest disappointment so far has been Suryakumar Yadav (scored 66 runs in total so far).
There is more to the game than just batting. Ishan Kishan is a good wk, we only recognize wicket keepers worth when you see one who is not good at it. He is having 33 avg runs per match so far with SR of 145 (
source), that's good for t20 format. Tim David in last match took 4 catches and 1 run out, had those catches were dropped Mumbai might not have won.
Also, not everyone may perform excellent in every match, but in that one game that they do, they become the reason for the win.
Batting, bowling, captainship, fielding, economy rate, wicket keeping — all these combined make a good team. Team who full-fills most of these wins the trophy.