World Cup 2015: England's Alex Hales has the 'X-factor'

Batsman Alex Hales is a player capable of being a match winner for his country in the World Cup, says England vice-captain Jos Buttler.

Hales has not yet featured in the tournament, but is tipped to play against Bangladesh on Monday with Gary Ballance struggling for runs.

"He's got that X-factor. It's something that's exciting when he walks to the crease," Buttler told BBC Sport.

"It's exciting to watch. He can take the game away from a team."

Hales, who was selected for three of England's seven one-day international matches in Sri Lanka last December, would likely open the batting for the must-win Pool A game in Adelaide on Monday.

Ballance is expected to be dropped with Ian Bell moving to number three.

"He's raring to go and put in a performance to show he feels like he should have been playing," Buttler said of Hales, who averages 18 from his seven ODIs to date.

England have won only one of their four matches in the tournament; beating Scotland and suffering heavy defeats to Australia, New Zealand and Sri Lanka.

This has left them fifth in the pool, three points behind Monday's opponent, who they must beat before also recording a victory over Afghanistan to keep alive their hopes of qualifying for the quarter-finals.

"It is a massive week for us," said Buttler. "Everyone is very honest and open that we haven't played well enough."

Buttler also defended the team after recent criticism from former player Kevin Pietersen, who suggested on Twitter that they are failing because they are too preoccupied by statistics.

"I don't think it would be a good place to get to," added Buttler. "The best thing we can do in one day cricket is use our instinct, use our initiative and back ourselves to read the game.

"We'd be doing ourselves an injustice to get to caught up in numbers and stop playing the game."