England midfielder Jordan Henderson has emerged as an injury doubt for Wednesday's World Cup semi-final with Croatia.
Henderson has started all but one of England's matches during their run to the last four but faces a race to be fit in time for their first semi-final appearance at a World Cup since 1990.
The Liverpool midfielder is suffering from a tight hamstring and will be carefully managed ahead of Wednesday's crucial showdown with Croatia.
Jamie Vardy also remains a doubt after missing the 2-0 quarter-final win over Sweden with a groin strain.
The England squad returned to training at their Repino base on Monday following Saturday's triumph and have a quick turnaround before Wednesday's match at the Luzhniki Stadium.
Henderson is currently on a run of 30 matches unbeaten for England, which is the longest streak of any player in the country's history.