Eoin Morgan steps in as England captain for just one match, because of Alastair Cook's ban - but is determined to put his stamp on the job all the same.

The Irishman has previously led his adopted country seven times in Cook's absence, through injury and prescribed rest, over the past three years.

This time, of course, another brief opportunity comes about via a disciplinary suspension following England's unacceptable over rate.

The stakes are high too for Morgan, as England try to follow up their victory in Hambantota with a second at the Premadasa Stadium tomorrow to level the score at 2-2 against Sri Lanka.

He badly needs an overdue personal contribution with the bat as well, having endured a miserable sequence of only 207 runs in his last 13 one-day international innings since his prolific series in Australia last winter.

Morgan, however, is not about to be suckered into changing his method - and is convinced he must also lead England instinctively rather than by committee.

"I've always done it my way," said the 28-year-old.

"Things won't change. I play it as I see it.

"If my way is different, then that's just the way it is."

As for his batting, in the absence of any evidence that he has developed a significant glitsch from his modes of dismissal over the past 10 months, Morgan will stick to what he knows.

He remains renowned as a middle-order game-breaker in all formats, but does concede he needs to strike a balance between committing to his best attacking shots and trying to get himself in.

"I'm a gambler - and I'd say I'm due," Morgan said.

"I've got to stay true to myself.

"I have to play an aggressive type of game. It's the way I play, the way I have done since I was a kid - and it works for me.

"So there's no use me going into my shell, and not playing any of my shots."

While batting, as well as leading the team, he will listen to himself more than others.

"The responsibility on me is to play my own game," he said.

"It's a great responsibility to have, because you've no obligations to people telling you what to do."

Morgan admits he found the going tough especially against India at the end of last summer.

But having dropped to number six in England's victory on Wednesday, to accommodate Ravi Bopara's promotion above him, he believes he is close to getting it right again - in a position which suits him fine.

"I've batted at number six before," said Morgan.

"I know very few people have scored a (limited-overs) hundred at number six - but I know I'm one of them.

"In the India series, I don't think I was good enough.

"I came up against a good side, and never managed to spend enough time at the crease to get myself in.

"(But) since I've come here, I've worked tremendously hard ... I think, given the opportunity, if I can get maybe 40 or 50 balls under my belt in the middle it will do me the world of good.

"I've only had three knocks here so far, and maybe have felt a little bit rusty.

"I (need) as much time as possible. If I chew up balls in the middle, so be it."

As England try to get a foothold at the start of their World Cup winter, Cook's enforced absence - albeit for just one match - is a complication.

It requires not just a new captain - England were quick to nominate Morgan - but also a rethink at the top of the order.

Morgan was giving nothing away about how those discussions may develop, but it seems a straightforward choice between apparent conservatism and adventure.

England could play safe, and perhaps canny, by asking Ian Bell - dropped two days ago - to return as a stop-gap for Cook, or could push Alex Hales up alongside Moeen Ali and give James Taylor a chance in the middle order.

Whatever the exact personnel, Morgan said: "We have a big job on our hands.

"I take a lot of confidence from the last game, given we probably didn't play our best cricket but got the result we wanted.

"You can see the belief in the guys' eyes.

"We've made strides since we arrived here ... we are starting to hit our straps, and hope we can continue our success in this next match."

Teams for the fourth one-day international between England and Sri Lanka at the Premadasa Stadium, Colombo, on Sunday, starting at 0430GMT:

England (possible): EJG Morgan (capt), MM Ali, AD Hales, JWA Taylor, JE Root, RS Bopara, JC Buttler (wkt), BA Stokes, CR Woakes, JC Tredwell, ST Finn

Sri Lanka (possible): A Mathews (capt), T Dilshan, K Perera, K Sangakkara (wkt), M Jayawardene, L Thirimanne, T Perera, J Mendis, R Herath, D Prasad, A Mendis.

Umpires: S Davis (Aus) and R Martinesz

Third umpire: S Fry (Aus)

Match referee: D Boon (Aus)