Moeen and Hales prepare for shoot-out

Alex Hales and Moeen Ali will each be given the chance to stake a claim to be Alastair Cook's opening partner for the Test series against Pakistan, according to Trevor Bayliss, England's head coach.

Speaking to the media in Dubai following England's first day of training since arriving in the UAE, Bayliss admitted that he had a "bit of an idea" about which of the two batsmen would fill the vacancy left by Adam Lyth's omission.

However, with two two-day warm-ups against Pakistan A taking place in Sharjah next week, England intend to investigate their options ahead of the first Test on October 13. The balance of the bowling attack, Bayliss added, is likely to be the decisive factor.

"I don't think we've got a definitive answer just yet," he said. "We've got a few days of practice and a couple of warm-up games ... before we select that [Test] team.

"It will probably get down, from a bowling point of view, to whether we want an extra spinner or pace bowler ... [then] do we want an extra batter? It could get down to one of those decisions, and who opens the batting could be a consequence of that.

"I think both those players will get an opportunity," he added. "We'll play the first [warm-up] ... and then see what we need to achieve out of that last match.

"It will probably be determined on how we play in the first one, and who needs an extra hit, who's had enough ... but I'm sure, especially those two boys, will get their opportunity."

Moeen, who currently bats at No. 8, has cemented his role as England's first-choice spinner, with 45 wickets in 16 Tests since his debut against Sri Lanka at Lord's in June 2014. However, he has opened the batting with some success in the one-day team and, on the slower surfaces of the UAE, his languid strokeplay could prove a useful foil to Cook's more attritional attributes.

His promotion would also allow England to hand a Test debut to Adil Rashid, the legspinner, without necessarily weakening their seam-bowling attack. James Anderson and Stuart Broad enjoyed plenty of personal success in the UAE on England's last visit in 2012, claiming 22 wickets between them despite being on the wrong end of a 3-0 whitewash. With back-up from Ben Stokes and one of Mark Wood or Steven Finn, pace is likely to play a significant part in the team's plans.

Rashid had been close to making his Test debut against Australia at Lord's in the summer when Moeen was struggling with a side injury. However, he withdrew from selection citing a sore finger, and hasn't yet had another opportunity to win his first cap despite impressing in limited-overs cricket for England.

Bayliss, however, believes his time is sure to come at some stage during the Pakistan series. Asked if Rashid was ready for Test cricket, he replied: "Yes, if he goes out and bowls like he did against Australia. He backs himself, he bowls aggressively to take wickets, bowls his variations. There's no reason why he can't be successful.

"I think he bowled extremely well during the one-dayers against Australia and took wickets. I think he'll make his debut. I'm only one of three selectors but that's my view - I think he'll play at some stage on this tour."

All of which could leave Hales on the outside looking in, and not just for this leg of the winter either. He had originally been earmarked as the more likely selection against South Africa in December, following Cook's suggestion earlier in the week that a horses-for-courses approach would be taken to England's two winter tours. Bayliss, however, appeared to offer a different view, one that was more consistent with the recent experience for England openers.

"Whoever does well here is going to be very difficult to drop," Bayliss said. "A lot of it is up to the individual player. Whoever gets the opportunity, if they nail that position then we go to South Africa with more than likely that player the partner for Alastair."

With the exception of Jonathan Trott, who retired from international cricket after a three-Test comeback in the Caribbean earlier in the year, each of Cook's batting partners since the retirement of Andrew Strauss - Nick Compton, Michael Carberry, Sam Robson and Lyth - was given at least five Tests to prove their worth.

Cook himself is one of four survivors of the 2012 Test series, alongside Anderson, Broad and Ian Bell, and he admitted that it would require some "blood, sweat and tears" for his squad to acclimatise to the oppressive desert heat ahead of the series opener in Abu Dhabi in just under a fortnight's time.

"On that last tour, we probably should have won that series," Cook said. "We had opportunities. We had to chase 140 on a good wicket, and we should have done that. Credit to Pakistan. They hung in there in that series, and then really won the critical moments well. That can be the way in these conditions - the game can turn very quickly.

"We will get used to it, but it is very warm. That's part of the conditions we've got to face, but it's the same for both sides. You just have to make sure you grab that opportunity. But we've got a young side, an exciting side. We're very clear in our mind how hard it is going to be - but what a challenge it is for us."

One additional factor for this series is England's recruitment of Mahela Jayawardene, the former Sri Lanka captain, as a batting consultant. As one of the best players of spin of recent times, his input on the conditions that the players will face is sure to be invaluable.

"To have Mahela on board with his experience, especially playing spin, and knowledge is a huge boost," Cook said. "He knows Trevor and Paul [Farbrace, assistant coach] very well so he's fitted in very well. He's scored over 25,000 international runs which is a hell of an achievement. It's down to our batters to pick his brains."