Mumbai Indians impact sub usage today or the idea behind it is really good. I’m not sure why Watto at the mid innings break was critical of it or why Manjrekar was criticising it during the game either.
If batting first:
Send Brevis in as the number three or four if you lose a couple of wickets in the powerplay or in the first six to seven overs for someone who got out, that way you’re getting extra batting depth and you’ve already got six decent bowling options in your lineup anyway.
Send Shepherd in if it’s the start of the death overs or during it if you’ve lost five wickets and your next batter has to be Coetzee, that way you get an extra hitter, an extra bowling option and a quality fielder.
Send Thushara or Mulani in (depending on the pitch being pace or spin conducive) if you’re almost at the end of the innings or finished it for the extra pure bowling option. Hell, you could decide based on matchups too.
If batting second:
There’s less flexibility here and you would have to play a bit of guesswork. Like their last game, the best use would be to send Shepherd in but during the first innings itself in place of someone who has completed their spell or offered enough to the bowling attack so that he can bowl a couple of overs in the middle to death overs and then stay down the order whilst batting for a death overs hitting role. The other alternative would be for Brevis to come in if you see the pitch is on the slower side and you would need an extra batter to help.
Ideally, you would want a batting all-rounder or an all-rounder capable of batting in the top six in this scenario with a powerplay specialist as part of the bowling attack. Your powerplay specialist bowls his allotted three to four overs in the first ten, bows out and is replaced by your all-rounder who then bowls an over or two before batting. Someone like Mo, Stokes or even Dre Russ would all work in this role. Again, there’s all sorts of tactical flexibility options in here for teams willing to experiment. Wonder which team will realise the potential present here and use it rather than sticking to the same tried and tested combinations.
I hope MI don’t abandon this idea anyway because it failed today, they were just unlucky to come up against Burger and Boult on top of their game.