India probably have the most fearsome top three of any ODI side at the moment, but their middle order has been a problem area since the end of the 2015 World Cup Wholesale Cigarettes Newport. MS Dhoni is no longer the explosive force he was in his pomp, and around him India have tried numerous options from Nos. 4 to 7, without quite settling on one combination. However, you cannot look at an alternative for Rayudu assuming that he won't do well. And if he doesn't do well overseas, there will be no time left anyway. The second guy in line for the No. 4 spot is Manish Pandey, who has hardly been tested over the last 12-18 months. He has not got enough opportunities to go one way or the other.
Dhoni is Dhoni. He is going to be there. India have left it way too late for anyone to earn their place in Dhoni's stead. Kedar Jadhav will be your No. 6 even though he is not your ideal finisher. He has been effective, but No. 6 is one place too low for him; yet I don't see that changing either. Rishabh Pant wasn't given enough opportunities, so we still don't know whether he can be an alternative for someone.