Haseeb Hameed has suffered a fractured finger a week before England are due to announce their Ashes squad.
The opening batsman retired hurt after he was struck by a delivery from James Harris during Lancashire's County Championship match against Middlesex at Lord's on Thursday.
Hameed returned to the crease and was unbeaten on 23 as Steve Finn took 8-79 to seal a 36-run victory for the defending champions on day three.
Lancashire later revealed that the 20-year-old sustained a break to a finger on his right hand.
Hameed played three Tests during the defeat in India last year, but his tour was cut short when he broke a finger in his left hand during the third Test.
The gritty right-hander has not played for his country since, but has returned to form in recent weeks to raise hopes that he could earn a place in England's touring party to face Australia.
England seamer Toby Roland-Jones was unable to bowl after damaging his side on day one of Middlesex's win in London.