Swann perplexed why Stoneman isn

Swann stunned by England selection

England's decision to pick Westley over Stoneman has the 60-Test veteran scratching his head

The decision by England selectors to pick Tom Westley over Mark Stoneman for the third Test against South Africa has stunned former spinner Graeme Swann.

Westley will make his Test debut and bat at No.3 at The Oval on Thursday after Garry Ballance was ruled out with a broken finger.

The 28-year-old won the coveted first-drop position despite owning an inferior County Championship record to Stoneman this season.

Westley’s numbers for Essex are impressive – 478 runs at 53 with two centuries and 106no for the England Lions against South Africa in a tour match – but Surrey’s Stoneman has 761 runs at 59 with three hundreds and a top score of 197.

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It’s those figures Swann points to when expressing his disbelief that Stoneman is not at least in the squad, with Dawid Malan the reserve batsman in the 13-man party.

"The most incredible thing is Mark Stoneman still not being given a chance," Swann said.

"Westley looks a good talent but they must know something I don't know because, why they have gone for him over Stoneman, there must be a reason behind it.

"His numbers have been immaculate over the last couple of years and I think it is very harsh on him he hasn't been picked in this squad.

"Tom Westley is a very good player and I have seen him a little bit and been impressed with him."

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While Swann is baffled by Stoneman’s omission, former England captain Nasser Hussain believes it a simple matter of batting style that won Westley the selection nod.

"The only thing that has stopped Mark Stoneman from making his Test debut next week is probably the fact that he is left-handed," Hussain wrote in the Daily Mail.

"Stoneman might have been just ahead of Tom Westley as a replacement for the injured Gary Ballance, but the fact that the top three would all have been left-handed matters.

"It’s all very well England saying they just need to pick their best players but they had to take into account how exceptional Morne Morkel and Vernon Philander are against left-handers."

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Westley will come in after left-handed opening pair Alastair Cook and Keaton Jennings, with the latter struggling for form after two Tests against the Proteas.

Jennings, the tall Durham southpaw, has 44 runs in four innings this series including scores of zero and three in the 340-run loss at Trent Bridge.

Swann says England’s top order is nowhere near settled.

"There are so many places up for grabs it is ridiculous," Swann said.

"You have the opening berth to go alongside Alastair Cook and the No.3 slot because Gary Ballance hasn't really worked out and has now broken his finger.

"He must be the most vulnerable man in world cricket at the moment."