England midfielder Frank Lampard faces a thigh scan after pulling up during training on Wednesday.
The 33-year-old, who recently joined up with the remainder of the squad after taking a week off after the Champions League final, will be assessed by the England medical staff tomorrow.
Liverpool midfielder Jordan Henderson has been put on standby following the scare, which could see Roy Hodgson without an experienced member of his squad.
Normal cirumstances would see a grade one thigh strain rule Lampard out for three weeks, meaning he would miss all three of England's group matches at Euro 2012.
Lampard has 90 international caps to his name, and is a veteran of two World Cup finals and one European Championships tournament.
The Chelsea midfielder recently played a pivotal role in helping The Blues win the European Cup, in a penalty shout-out against Bayern Munich, the first in the club's history.
Lampard missed England's first warm-up game prior to Euro 2012, the win over Norway, but was expected to feature in the second game against Belgium at Wembley on Saturday.
In his absence, captain Steven Gerrard was paired with Scott Parker in the centre of midfield, and the duo can now expect to form the back-bone of England's team in Poland and Ukraine.
With the England squad including some inexperienced faces, including Alex Oxlade-Chamberlain, Danny Welbeck and Phil Jones, Lampard is one of the more experience heads, and was expected to lead England through a Euro 2012 campaign for which they've enjoyed little preparation time.
Hodgson has placed Henderson on standby, despite a disappointing campaign for the Reds midfielder.
Should Lampard be ruled out, the loss is likely to spark renewed calls for the inclusion of Manchester United pair Paul Scholes and Michael Carrick, both of whom were left out of the original 23-man squad for contrasting reasons.
While Hodgson revealed that he never approached Scholes over coming out of international retirement, the England boss said that Carrick had informed The Football Association of his intension not to be involved as a back-up player.
Although the 30-year-old would have been called upon as a standby player, given the predicament England's midfield finds itself in, following Gareth Barry's withdrawal, Hodgson may be tempted to call on Carrick before flying to the team's Krakow base on 6 June.