Australia's Steve Smith was out for 92 after resuming his innings having been forced to retire hurt when he was struck by a short ball from England fast bowler Jofra Archer on the fourth day of the second Ashes Test at Lord's on Saturday.
Smith was on 80 when he was hit on the neck by Test debutant Archer, who bowled a hostile spell from the Pavilion End during which his deliveries reached speeds of well over 90 miles per hour.
Smith, who made 144 and 142 in Australia's emphatic victory in the first Test, had defied the England attack again as the touring side replied to the hosts' first-innings total of 258.
He was given a standing ovation by the crowd at the home of cricket as he walked off the ground before returning to the crease about 40 minutes later following the dismissal of Peter Siddle.
"Steve was hit on the neck below the left ear," Cricket Australia said in a statement. "He was assessed lying on the pitch at the instructions of team doctor Richard Shaw.
"Dr Shaw made the precautionary decision to remove Steve from the field of play to have him further assessed under Cricket Australia's head impact protocol. Steve then passed his assessments and will now be monitored on an ongoing basis, as is routine."
Smith showed he was suffering no serious ill-effects by hitting Chris Woakes for two successive boundaries, but he misjudged a straight delivery from the same bowler and was adjudged lbw.
It was the seventh Ashes innings in a row that Smith has passed fifty, a record in Test matches between England and Australia.
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