Chelsea will be without Ashley Cole for around three months after the England defender fractured his left ankle in Wednesday's 2-1 defeat by Everton.
The 29-year-old left-back limped off in the second half after a challenge by Everton's Landon Donovan.
A scan on Thursday revealed the full extent of Cole's injury.
It leaves him with a fight to regain his fitness in time for this summer's World Cup, with England's first match against the United States on 12 June.
Cole has been in superb form for Chelsea this season and his absence will be a blow to Blues boss Carlo Ancelotti, who saw his side's lead at the top of the Premier League cut to one point after their defeat at Goodison Park.
Yuri Zhirkov could deputise at left-back although Paulo Ferreira, predominantly a right-back, is versatile enough to play anywhere across the backline.
Cole could be back in action by mid-May but it leaves him only a handful of games before the finals in South Africa get under way.
And he will definitely miss England's only scheduled friendly before the World Cup, against Egypt at Wembley on 3 March, although there are plans to arrange another game against Mexico ahead of the finals.
That means Manchester City's left-back Wayne Bridge, who was caught up in the scandal that led to John Terry being stripped of the England captaincy last week, is likely to come into the reckoning.
Terry has been given time off by Chelsea and will miss Saturday's FA Cup tie against Cardiff after flying to Dubai to visit his wife.
The 29-year-old left-back limped off in the second half after a challenge by Everton's Landon Donovan.
A scan on Thursday revealed the full extent of Cole's injury.
It leaves him with a fight to regain his fitness in time for this summer's World Cup, with England's first match against the United States on 12 June.
Cole has been in superb form for Chelsea this season and his absence will be a blow to Blues boss Carlo Ancelotti, who saw his side's lead at the top of the Premier League cut to one point after their defeat at Goodison Park.
Yuri Zhirkov could deputise at left-back although Paulo Ferreira, predominantly a right-back, is versatile enough to play anywhere across the backline.
Cole could be back in action by mid-May but it leaves him only a handful of games before the finals in South Africa get under way.
And he will definitely miss England's only scheduled friendly before the World Cup, against Egypt at Wembley on 3 March, although there are plans to arrange another game against Mexico ahead of the finals.
That means Manchester City's left-back Wayne Bridge, who was caught up in the scandal that led to John Terry being stripped of the England captaincy last week, is likely to come into the reckoning.
Terry has been given time off by Chelsea and will miss Saturday's FA Cup tie against Cardiff after flying to Dubai to visit his wife.
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