Nathan Buck will play no further part in the ongoing Specsavers County Championship match against Worcestershire which began yesterday.
Buck was struck in the head while batting in the last over of play on Day 1 and retired hurt, bringing an end to the day’s play.
Club physio Barry Goudriaan ran through concussion testing with Buck after play and on the morning of Day 2 and removed the fast bowler from the match as a precaution.
Blessing Muzarabani comes into the side as Buck’s concussion substitute. Muzarabani can bat and bowl without restriction, including batting in Northamptonshire’s first innings.