The Wigan striker sat out Wednesday's training with a back injury and is a doubt for the World Cup qualifier against Kazakhstan on Saturday.
England also play Belarus next Wednesday.

Coach Fabio Capello has a range of striker options but is expected to pair Heskey with Wayne Rooney.
And the Latics star has been backed to play a key role by club chairman Dave Whelan.

He believes Heskey helps make the national side a more cohesive attacking unit.
And Whelan holds the ex-Liverpool star in such high regard that he thinks it was his absence through injury that cost England a place at last summer's European Championships.

Whelan said: "Emile has been absolutely terrific for Wigan but he has been unlucky with injury.
"I honestly believe his injury last year cost England their place in the European Championships.

"England are a better side and a more potent threat on goal when Heskey is playing up front.
"He has an ability to create things for his team-mates and to cause problems for the opposition."