The absence of the new vice-captain would exacerbate the loss of experience from the retirements of Michael Clarke and Chris Rogers, posing an even bigger challenge for new captain Steve Smith.

While Warner has not been ruled out of the two-Test series, which begins on October 9, he expressed pessimism about his chances of regaining fitness in time for it - and said he had felt that way ever since he was struck by the bouncer from England's Steve Finn with the second delivery of Saturday's second one-dayer at Lord's. He said it was similar the pain he felt the previous time he fractured his left thumb, in January 2013 facing Mitch Johnson in the WACA Ground nets.

"I knew pretty much straight away when I got hit that it was the same one and it was quite painful," he said on Sunday, having travelled from London to Manchester with the squad to fulfil a charity engagement on Sunday night. He will fly home to Australia on Monday.

"Look, I know from last time when it was actually just a minor fracture, it was a minimum of three weeks before I could pick up a bat.

"You never want to miss a Test match ... but it's probably highly unlikely I'm going to make Bangladesh."

Warner then confirmed he was bracing to miss both Tests, not just the first one on Chittagong. The second begins in Dhaka on October 17.

"At the moment it's six weeks with the thumb ... that's before I can pick up a bat, so I think that pretty much sums up what I can and can't do, so for me it's about trying to target what's after that and sit down with obviously the coach and the selectors and see what I have to do."

If Warner's expectation is correct it would delay his first Test appearance as Australia's vice-captain. It would be the first time he has been sidelined from Tests due to injury since his debut in November 2011.

"Any time you miss a game for Australia, Twenty20, one-dayer or a Test match [is is a blow] - in this case it's going to be Test matches and I'm quite disappointed," he said. "I've got another opportunity [to be vice-captain in Tests] when we come back to Australia, but I've got to try and do whatever I can to get this thumb ready to go."

Shane Watson's Test retirement on Sunday ended any possibility of him being asked to temporarily return to the top of the order. Rogers, who has just turned 38, made clear last month that he thought it was the right time for him to retire from international cricket, and would be almost certain to rebuff any request for him to consider a short-term comeback for the Bangladesh tour.

Joe Burns' selection as Warner's opening partner for the one-day series, despite an unexceptional domestic one-day record, was a positive portent for his chances of returning to the Test team for Bangladesh, as Rogers' successor.

Among other experienced contenders, Shaun Marsh impressed in the West Indies but had a horror sole Test in the Ashes. Usman Khawaja has not played a Test since the 2013 Ashes but was recently made Australia A captain for a tour of India.

If selectors choose Burns, who played two Tests and last summer, and uncapped Bancroft, or uncapped veteran Michael Klinger, who on Sunday notched his eight century of the English county season, it would be the most inexperienced Australian openers since 1979-80. Then, against England at the WACA Ground, Julian Wiener was on debut and Bruce Laird was playing just his second Test.

Given the departures of Rogers and Clarke between the Ashes and Bangladesh tour, Smith said the prospect of also missing Warner for at least part of the tour in Bangladesh had not dampened his enthusiasm for it.

"I'm really looking forward to it to be honest. I can't wait to captain Australia in Test cricket, and hopefully I'll be able to have a few senior players around to lean on," he said.

Warner said he would have faith in whoever selectors choose to replace Rogers and, most likely, himself for the Bangladesh Tests, and would be eager to assist them if asked.

"I think it'd be nice if I can have a little bit of a chat to whoever is there, but with the experience with Steve Smith who has been over there and a couple of other lads that they can actually learn from them," he said. "I'm pretty sure the guys that are coming in, [if they are] guys from Australia A they've just played in India and know what the experiences are like, so whoever comes in I'm sure will do a great job and do whatever they can to help the team win."