Frank Lampard gave England an injury scare on Saturday afternoon after being forced off in Chelsea's Barclays Premier League win against Norwich.
Lampard was withdrawn midway through the second half at Stamford Bridge after starting and scoring in a 4-1 victory.
The 34-year-old was in line to captain England in their World Cup qualifying double-header against San Marino and Poland, but Chelsea boss Roberto Di Matteo said after the game: "We'll have to assess him tomorrow and then see. He felt a little bit of a problem behind his knee, so for precaution, we took him off."
