The Irishman, who has just once before led his adopted country - against his native one, in a one-day international - steps up again, because regular captain Stuart Broad has gone home injured. Morgan spent much of the past two months on the periphery of the Test squad, as England famously won in India for the first time since 1984-85.
The middle order batsman will be unfazed by his sudden shift into the limelight - because he has made it his business to be ready to do so. Asked if it is a difficult adjustment, he said: "I don't think so. Being vice-captain of the Twenty20 side in the first place, you're always going to be thrust into a situation where the captain might get injured."
Morgan continued: "It's not that I've prepared for it, but mentally you think if something happens to Broady then you might get the chance. Really, I'm quite happy to take the reins."
England lost by an embarrassing 90-run margin when they were bowled out for a record low score of 80 in their last Twenty20 meeting with India. That came in Colombo three months ago during the failed defence of their ICC World Twenty20 title, and on Thursday they will make at least four changes as they choose from an especially young squad.
Morgan hopes the success of the Test team can pass on a winning momentum too.
He added: "Absolutely, as we've seen in the past when the Test side has done well, it's had a knock-on effect with the other two teams - and certainly we'll be looking to win these two games and take confidence and momentum from the Test side and keep the winning habit up."
Morgan senses the combination of high morale after the Tests, and an influx of players with much to prove, will make his job enjoyable.
"I think generally, when you're in a side and you get new guys coming in, they do bring a buzz and a new energy," he confessed. "The fact the team has changed so drastically, I think that energy is evident around the hotel at the moment.
"If we can take that into the game and stay cool and calm and back ourselves to produce our skills, I think we'll be all right."
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