Frank Lampard has emerged as a major doubt for England's Euro 2012 campaign and faces a crucial scan to determine whether he can travel with the squad.
The Chelsea midfielder suffered a thigh injury during a training session with England on Wednesday and there are concerns within the national team camp that the 33-year-old will be unfit for the tournament.
Should the worst fears be realised, England would be left reeling from the second withdrawal of an experienced midfielder this week, after Manchester City's Gareth Barry was forced to pull out with an abdomen injury. Barry was replaced by Everton defender Phil Jagielka, and Lampard's place would go to Liverpool's Jordan Henderson.
Although manager Roy Hodgson had to submit his final squad of 23 with UEFA on Tuesday, he is permitted to replace an injured player after that deadline.
If Lampard is ruled out by injury, it would be a cruel blow for a player who returned to favour at Chelsea under Roberto Di Matteo over the closing months of the season, winning the FA Cup and Champions League with the Blues.
Participating at the European Championship in Poland and Ukraine was looking uncertain as Lampard became a bit-part player at Stamford Bridge under former manager Andre Villas-Boas.
But the change of manager transformed his fortunes, and Lampard has been looking forward to playing a key role for his country this summer.
Speaking prior to his injury, Lampard, who turns 34 next month, said: "I did wonder if I was going to make it (the Euros) earlier in the season. I'm not silly. I wondered if I'd be out.
"I took nothing for granted at that stage and it just shows you how football can turn, not just for myself.
"A few in the squad might have been out of the picture a few months ago and now they are in the picture. I can only be thankful that I just kept going through those times."