England captain Eoin Morgan expects batsman Jason Roy to be fit for the Twenty20 and ODI series against Australia next month.

It was confirmed on Thursday that Roy would miss the upcoming T20 series against Pakistan due to a side strain he sustained in practice this week.

Roy will remain with the England set-up while he recovers, and will undergo rehabilitation ahead of the Australia white-ball series, which starts on September 4 in Southampton.

Though he will be shorn of one of his big hitters at the top of the order, Morgan is confident Roy – who made only 25 runs across three ODI innings in the recent series against Ireland – will return in time to face Australia.

"Unfortunately he tweaked his side two days ago, and will be ruled out for the three games in order to give him time to prepare for both series against Australia," Morgan told a news conference.

"At the moment we don't anticipate it being anything serious but we want to give him every chance to be fit for Australia, both series - T20s and 50 overs.

"So we'll see how he progresses over the next three or four days and be able to report back then."

Despite Roy's injury, England have not yet called up an official replacement, with Morgan feeling there is enough quality cover within the squad already.

"At the moment, given that we have a lot of flexibility, particularly with our allrounders in Joe Denly and Moeen Ali, and the reserve batters in the squad, at the moment we don't feel a need to pull anybody in for tomorrow," he added.

Liam Livingstone, Tom Banton and Dawid Malan appear to be the likely candidates to battle it out to take Roy's place.

"Dawid in particular has really put together an early establishment of a career that, every time he's available, he's put himself forward as the next man, simply by weight of runs and the rate at which he scores them," Morgan said.

"[Banton] naturally is a top-order batter, but at a time where we have top-order batters in abundance and actually lack middle-order players, it's sometimes difficult to get him in in the position that is his strength.

"We know what he can achieve at the top of the order, along with a number of other guys who bat in the top five. And so hopefully if he gets a chance he can take it."