Somdev is up against world number 13 Mikhail Youzhny in the first match on Sunday and his win is imperative for India to dream of a win.
"Somdev's match is very critical for us. Youzhny is a higher ranked player but reputations won't count if Somdev plays well. He has nothing to lose and can go all out," Misra said.
The non-playing captain said he would be tempted to play Paes in the second reverse singles in place of Rohan Bopanna If Somdev go on to make it 2-2.
"If Somdev wins then we have the option of Paes playing in the second singles, which will become decisive. I have that option in mind although Paes hasn't played singles for a long time. But he has the game to win singles even today," he said.
Misra was extremely happy with the way Paes and Bhupathi beat Igor Kunitsyn and Teimurza Gabashvili on Saturday.
"They played superlative tennis. They have not played that good in recent times. They combined well. The other guys were not bad but Leander and Mahesh did not give them any chance," Misra said.
Misra, himself a former Davis Cupper, said he did not expect such an easy win for India on Saturday in the dobles rubber.
"I thought of stiffer fight but our players were on top of the game. They served well, volleyed well and had total control over the match," he said.
Paes and Bhupathi had an easy 6-3 6-2 6-2 win over their rivals.
The skipper though was candid to admit that the hosts are overwhelming favouriotes to win and advance to the quarter-finals of the elite World Group on Sunday.
"Yes, Russia are favourites tomorrow to close the tie in their favour tomorrow. But we are underdogs and sometimes it helps," he said.