Graham Onions’s chances of playing in the first Test against South Africa receded further on Wednesday when he was unable to train on the eve of the match at the Oval because of a hamstring strain. The Durham seamer, included in England’s 13-man squad as an extra pace bowler, was not involved in Wednesday morning’s net practice. He has not yet been ruled out of contention to play when the first of a three-Test series starts here on Thursday, but the injury has not done his prospects any good.