England on defensive over Hales

England have been forced on to the defensive after just a few days in Sri Lanka, with Alastair Cook and Peter Moores having to explain the decision to leave Alex Hales out of Friday's opening warm-up match.

Ahead of seven ODIs against Sri Lanka, England appear to have taken the cautious approach once again by promoting Moeen Ali to open alongside Cook. Moeen, like Hales, is still finding his way in ODI cricket but offers a spin-bowling option that has edged him ahead. He is also a classy batsman but without the same concussive approach as Hales, the only England batsman to have scored a T20 hundred.

With Cook a certainty at opener and Ian Bell seeking to establish himself at No. 3 - having been demoted to accommodate Hales during the one-day series against India - England have decided they cannot afford to have another specialist batsman in the top order. The full XI to play Sri Lanka A has not been announced but Joe Root, who bowls offspin, is likely to bat at four, with an allrounder, probably Ravi Bopara, at six or seven.

"It was incredibly hard to pick a side even for this warm-up game," Cook said. "We just wanted another bowler in top six, and Moeen gives us that option. It's a real tough call on Alex ... But we're nowhere near making our final decision."

Hales is still likely to get his chance in Sri Lanka but, with a maximum of 12 ODIs before England begin their World Cup campaign against Australia in Melbourne, there is little room for manoeuvre. The Nottinghamshire opener made his one-day debut in August, three years after coming into the T20 side; during that period, he became the No. 1-ranked batsman in T20 internationals and earlier this year hammered an astonishing 116 from 64 balls against Sri Lanka to give England their only victory at the World T20.

Moores suggested that Hales' performances against India, when he scored 92 runs in four innings at a strike rate of 68.65, were partly behind the decision to try out Moeen.

"Alex has progressed quickly. The fact he has managed to climb to number one in the world as a T20 player means there is a lot of talent there, and explosive talent at that," Moores said. "He had some exposure in the one-day arena against India, where he would have learnt a lot. When you play international cricket and come up against the same team time and again, people will always find a kink somewhere and the key is how you adapt.

"India started to bring the ball back into Alex and bowl spin at him, so he has to decide what else he is going to come back at them with."

England play two 50-over warm-up matches before the first ODI on Wednesday and the questions over selection are a precursor to the debate about their best World Cup XI. Secondary skills such as bowling and fielding will come into it but, while Moeen's ability to play a full role with the ball will come in especially useful on the subcontinent, that may not turn out to be such an important consideration in Australia and New Zealand, where the World Cup will be played.

"There are certain places for lads to fit in and that is about taking opportunities,'' Moores said. "This tour is about winning, and people taking their games on. We've got two practice games to try and win but to also look at some options we've got. We've then got a tough decision to pick the ODI team - and it is very tight."

One issue that has contributed significantly to England's tentative World Cup approach has been the form of Cook and a return to significant run-scoring for the captain would help ease their mental load. Cook has not scored an ODI hundred since 2012 and over the last two years he has averaged 33.24 from 30 innings, at slower than his career strike rate. His presence in the side is seen by some as a major obstacle to success but Moores is part of an equally staunch group backing Cook to produce a response.

"He's been around the block a lot," Moores said. "He's been under pressure before and he's often responded to that pressure really well. We know he's a steely character and a very good player."