LONDON: England match-winner Eoin Morgan said he'd made a “big start” for his summer after his unbeaten 89 set up a 15-run win over Australia in the first one-day international here at Lord's.

The hosts, who if they sweep this series 5-0 will knock Australia off their perch at the top of the 50-over standings and be number one across all three formats, were faltering at 121 for three in difficult conditions when left-hander Morgan walked out on his Middlesex home ground.

He then demonstrated the skill and nous that has won him a reputation as a one-day 'finisher' with a 63-ball innings featuring four sixes and five fours to get England up to a respectable 272 for five.

England's four seamers -- with James Anderson suffering a degree of groin trouble --built upon Morgan's good work by taking two wickets apiece as Australia, despite fifties from captain Michael Clarke and opener David Warner, were held to 257 for nine.

For Morgan, who saw England captain Alastair Cook and Ian Bell share an opening partnership of 74 made across several rain breaks, there was the satisfaction of playing a major international innings once again.

He was dropped from the Test side after struggling against Pakistan in the United Arab Emirates in January and February.

And the 25-year-old former Ireland international was then reduced to a bystander in the Indian Premier League as he failed to play a single match this season for champions Kolkata Knight Riders.

“It's not fun when you're not getting any runs, not contributing to the team. So today was a big start for my summer,” said Morgan.

“When I came back from Dubai, I had two weeks off and came back and reflected on what I'd done poorly in the UAE and made some technical changes.

“One of them was the balance of my head, and the other was my hand movement.

“The stuff I did was very basic. It's just a matter of monitoring it.”

But an admiring Cook was in no mood to downplay a Morgan display that set up England's seventh straight one-day international victory.

“To score at a strike rate of 130 or 140 is an incredible innings,” said Cook.

“Clearly, it was hard work to start with at the top.

“The ball was nipping around a bit, but what was pleasing is that we didn't panic as a batting order.”

Clarke top-scored for Australia with 61 and, with wicket-keeper Matthew Wade, got his side back into the game with a brisk stand of 57.

However, a dreadful mix-up saw Wade run out as he sacrificed his wicket on behalf of his skipper.

“It was disappointing -- and run outs tend to do that, don't they? They tend to cost you the game,” Clarke said.

Clarke praised Morgan's innings but also highlighted aspects of Australia's game requiring improvement ahead of Sunday's second one-dayer across London at The Oval.

“He played really well, that's for sure, and helped England get to a very good total,” Clarke said.

“We probably didn't execute our skills at the death as well as we could have. I think they took 80-odd off the last 10 overs.

“Then we lost wickets at important stages of the game, where we needed blokes to go on and make big scores.

“We were a little bit impatient, but that's what good bowling does. It builds pressure and it makes you impatient.”