The England batsman Kevin Pietersen is to fly home from the one-day series in Pakistan after struggling to overcome a rib problem.
The Hampshire player visibly struggled in yesterday's defeat in the second match of the series, having earlier aggravated a previous injury, and he left the field before the end of play.
England's backroom staff had hoped to Pietersen would be able to continue to be involved in the tour after a cortisone injection but that has not proved to be the case.
The South African-born batsmen's departure is a big blow to England as they look to salvage something from what has been a disappointing tour to the sub-continent.
Pietersen forms a key part of England's one-day strategy by providing an explosive middle-order partnership with all-rounder Andrew Flintoff.
No replacement will be called up for the remaining three one-day internationals, with the series level at 1-1.
The ECB's chief medical officer, Dr Peter Gregory, said: "Due to a series of events that aggravated a previous rib problem during practice and the first two one-day internationals Kevin is returning home to the UK and will play no further part in the one-day series.
"Scans taken after the first one-day match showed no fracture but demonstrated a stress lesion and despite passing a fitness test ahead of the second one-day match Kevin suffered intolerable pain throughout.
"A stress lesion of this nature is likely to require four to six weeks rest but it is expected that Kevin will make a full recovery in time for the tour to India in March next year."
Pietersen said: "It's very disappointing to be leaving the England team at this time as I was looking forward to a strong one-day series. I hate missing matches and despite trying to play the first couple of one-day games the pain was just too great.
"I certainly wouldn't want to let my team-mates down due to injury, whether it is with the bat or in the field, so the only choice available to me is to rest the injury with a view to a full recovery in time for India."