England captain Harry Kane will go for a scan on his ankle ahead of the Three Lions' next World Cup encounter against the United States.
Kane was brought down in a heavy challenge by Morteza Pouraliganji three minutes into the second half of England's 6-2 thrashing of Iran on Monday.
After some treatment, the striker picked himself up and continued until the 75th minute, when he was replaced by Newcastle forward Callum Wilson.
Kane was seen limping after the match with his right ankle strapped, though manager Gareth Southgate appeared unworried over the striker's fitness, saying he was replaced because the game was already won.
But the Tottenham star will now have his injury assessed, causing concern over the talisman's availability for England's second Group B fixture against the USA on Friday.
The 29-year-old registered two assists before making way for Wilson as England ran riot against Iran and would be a huge miss for Southgate if his ankle injury proves serious enough to rule him out.
Kane is just two goals away from equalling Wayne Rooney's 53 goals as the Three Lions' all-time top scorer.