Ballance injury confirmed as broken finger

Are changes needed in England's top six? (1:15)

Mark Butcher questions whether wholesale changes are needed in England's top six after their defeat to South Africa in the 2nd Test. (1:15)

Gary Ballance has been ruled out of the third Investec Test against South Africa at the Kia Oval after fracturing his left index finger.

Ballance was struck on the finger by a short ball from Morne Morkel on the fourth and final day of the Trent Bridge Test. He went for an X-ray on Monday night and was told the results on Tuesday.

He saw a hand surgeon in Leeds on Tuesday evening, when the diagnosis was confirmed. He will continue to be monitored by the England medical team and could still be available for selection in the fourth Test at Old Trafford next month..

But with the third Test starting on Thursday week, Ballance was never likely to recover in time, despite being willing to play through the injury. He has a top score of 34 in the series to date - and an average of 21.25 - and his position was far from secure anyway.

Surrey's Mark Stoneman is the most likely replacement. Trevor Bayliss, the England coach, admitted after Trent Bridge that Stoneman and Essex's Tom Westley had been discussed as options ahead of the series and should be considered "on the edge" of the team.

Stoneman, who made half-centuries in both innings of England Lions' match against South Africa A, could bat anywhere in the top three, providing an opportunity for Keaton Jennings to slip down to No. 3 if required.

His selection will do nothing to appease Durham supporters who feel that 'more fashionable' clubs receive more attention from the England selectors. Stoneman, 30, spent a decade at Durham but may well find that, only a few months after moving to Surrey, the selectors' attention has been grabbed. He is averaging 58.53 in the Championship season with three centuries.

He has been left out of Surrey's side for the last couple of T20 games and is understood to be training only against a red ball at present.

Bayliss, who admits he has never yet seen Stoneman bat in the flesh, had previously indicated that he was reluctant to consider making too many changes as it be inconsistent with policy of recent months. He might also have hinted, depending on your interpretation of his words, that England's problems in finding a top-order partner for Alastair Cook may be due to the quality of batsmen being produced by county cricket.

"Since Andrew Strauss, I've forgotten how many guys have played at the top of the order," he said. "All of those guys have been picked because they've done well in county cricket.

"They've then probably started off well in Test cricket and then fallen away a little. So that's a concern, obviously.

"But one of the things we've tried to do since I've come in is give those guys a bit longer to show what they have. It still hasn't worked, to be honest. But if we're consistent with our selections Jennings, at the top of the order, should get some more goes.

"The last selection meeting we had before this series started, players like Stoneman and Westley were spoken about at length. Obviously, Haseeb Hameed, too, but he is a little out of form this year. So those guys, they are on the edge."

Bayliss had previously seemed to reject the idea of bringing in a new man to bolster the batting. He suggested a side should not require eight batsmen and that Moeen Ali, in particular, would be peeved by being demoted down the order yet again.

"The one I'd be concerned about the most is Moeen," Bayliss said. "As a batter, I'd be upset having to bat No.8.

"It's almost a waste having eight batters in the team. We played that way against Australia and were successful because Moeen, as a batter at No.8, scored a few runs.

"But in a way, that's papering over the cracks a little. It's saying we're not confident with our batting line-up. The simple fact is we've got to do better with the bat."

While Bayliss strongly refuted any selection that England paid for playing overly aggressively - "If you look at the top seven, we had five blokes out blocking," he said - he did admit he was concerned by England's inconsistency.

"If you look back over the couple of years I've been here, we've won one well and then lost one well," he said. "It is a concern.

"I put the questions to the team: if we win a game, does our mindset change? So we approach the next game differently? It's only them that will be able to say as a group or as individuals. But we'll go away over the next few days and when we get together again I'm sure we'll sit down and have another discussion about it.

"The white ball team is a lot more lot more settled. In fact we have other guys who could quite easily be in the team. It's not quite like that in the red ball team. There are still a number of guys trying to cement a spot, which always creates a little bit of pressure.

"The one thing we have - and we certainly admit - is that whether you're an attacking style player or a defensive type player, we've got to do it better. Definitely."

England are also expected to provide an update over Mark Wood's fitness imminently. He suffered bruising on his left heel during the second Test and may be sent for a scan to assess the extent of the damage. Wood has undergone three bouts of surgery on his left ankle.

The squad for the third Test is due to be named on Friday or Saturday.