England striker Wayne Rooney aggravated a groin injury while playing for Manchester United on Sunday, a month before the World Cup begins.
The 24-year-old Rooney limped off in the 77th minute of United's season-ending 4-0 victory over Stoke.
"I don't think it is serious - he should be OK for England," United manager Alex Ferguson said.
Hampered by groin and ankle problems for more than a month, Rooney had initially been ruled out of the final two matches of the club season but returned for United's failed bid to win a fourth straight Premier League title.
Rooney, who scored 34 goals for United this season, rejoined his teammates on the pitch after the match for an end-of-season lap of Old Trafford.
Rooney is certain to be in the provisional 30-man World Cup squad announced Tuesday by coach Fabio Capello. But it is unclear whether he will play in England's friendlies against Mexico on May 24 and Japan on May 30 before the final squad of 23 is announced on June 1.
The team's first match of the tournament in South Africa is against United States on June 12 in Rustenburg.
England captain Rio Ferdinand completed a full match against Stoke in a season blighted by a chronic back problem.
Gary Neville also played 90 minutes. Ferguson recently suggested the 35-year-old right back could return to the England squad. Neville's last international appearance came in February 2007.
United midfielder Owen Hargreaves wants to go to South Africa. But despite making his first appearance in 19 months last weekend - in which he didn't touch the ball - England's key player from the 2006 World Cup didn't play Sunday.
