Haseeb Hameed, a contender for England's Ashes tour to Australia, suffered a fractured finger batting for Lancashire against Middlesex at Lord's on Thursday.
The opener retired hurt after being struck on the glove by James Harris on the third day of the First Division match.
Hameed's injury came just two days after Middlesex seamer Toby Roland-Jones, a likely candidate for a place in the Ashes squad, suffered a lower back problem requiring scans to discover the full extent of the damage.
The 20-year-old Hameed had to fly home early from England's tour of India late last year for an operation on a broken left hand.
He has yet to add to the three Test caps he won in India following a poor start to the domestic county season.
But with England still having several doubts over top order positions, Hameed has been touted to be included in the Ashes-holders' squad for a five-Test series starting in November.
Thursday saw Hameed resume his innings in a bid to stave off defeat but he was left not out as Middlesex completed a 36-run win.
England's selectors now face an anxious wait to discover the extent of Hameed's injury, with the Ashes squad due to be announced next week.