The 34-year-old came to decision after day two of fourth Test defeat at Trent Bridge
The skipper 'didn't think England were quite ready' to beat Australia.
Alastair Cook's side complete victory by and innings and 78 runs to reclaim the urn.
England are on the brink of regaining the Ashes after another Australia collapse.
The 'perfect start' to the fourth Test of the Ashes was 'one of those days you dream of,' says Stuart Broad
England take a giant stride towards regaining the Ashes as Australia are humiliated.
Cook also said that he is hopeful seamer Mark Wood will be fit to play in the fourth Ashes test at Trent Bridge.
Former Pakistan cricketer Wasim Akram's car was shot at in Karachi.
IBTimes UK sports editor Nick Howson previews the 4th Ashes test at Trent Bridge.
Durham fast-bowler fit to play at Trent Bridge; Lancashire paceman recovering well from side-strain.
Australia will face England in the fourth Test of the 2015 Ashes. Find out how to follow the match live in the UK.
England try to secure an Ashes series victory at Trent Bridge.
Shane Warne says James Anderson's injury will be a huge blow for England against Australia in the fourth Test.
James Anderson misses out after suffering a side strain.
England selectors will meet on 1 August to select squad for Trent Bridge match.
Alastair Cook hailed Ian Bell after the batsman returned to form to help England win the third Ashes Test.
Ian Bell scores 65 not out as England storm to victory at Edgbaston.
The Lancashire seamer will be assessed before fifth Test at the Oval.
David Warner is hopeful that Australia can pull off a great escape and win the third Ashes Test.
Finn takes 5-45 as England close in on taking a 2-1 series lad at Edgbaston.
This comes despite claiming his best ever Ashes figures of six for 47 on day one of the third Test.
Brad Haddin failed to make it to the playing XI as Peter Nevill was selected ahead of him for the third Ashes Test.
Australia are bowled out for just 136 on day one at Edgbaston as England take command.
Hosts are looking to bounce back after the humiliation suffered in the last test.
Former West Indies fast bowler says the Edgbaston pitch needs to support seam movement.
IBTimes UK sports editor Nick Howson previews the third test of the 2015 Ashes series.
England face Australia in the third Test of the Ashes series on Wednesday. Find out how to follow the match live in the UK.
Richards hopes Edgbaston will deliver a faster pitch to give more help to England's fast bowling attack.
The 37 year old underwent further tests on 22 July ahead of third Test at Edgbaston.
There is just one change in the England set up after a humiliating second test defeat at Lord's.