Everton striker Andy Johnson will undergo ankle surgery at the end of the season, which could rule him out of England's next European Championship qualifying match.
Johnson is playing with an injury to his right ankle, but the operation would be on his left ankle, Everton said Wednesday.
England plays Brazil in a friendly on June 1 at Wembley. Five days later, England travels to Estonia for a Euro 2008 qualifier.
"After injuring his right ankle, we were hopeful that the subsequent period of rest would help his left ankle," Everton head physiotherapist Mick Rathbone told the club's Web site. "However, that has not been the case and the player will have an operation as soon after the final match of the season as possible. Andy has had the problem for a number of months now and it is getting no better."
Everton's final game of the season is at Chelsea on May 13.
Also Wednesday, Everton strikers James Vaughan and Victor Anichebe signed contract extensions until 2011.
The 19-year-old Anichebe has scored four goals this season after starting six games, while the 18-year-old Vaughan has scored four from five starts. Monetary details were not disclosed.