NORWICH City will be without key forward Josh Sargent against Saints due to concussion protocol, manager Philippe Clement has confirmed.
The USA international was forced off in the first half of Norwich's 1-1 draw at Sheffield United on Tuesday, ruling him out due to strict concussion rules.
Saints head coach Tonda Eckert had planned to face Sargent anyway, and has also been left waiting to discover Mathias Kvistgaarden's availability.
The Danish striker, who scored three times in November, could lead the line for Norwich in Sargent's absence, but is a doubt due to a knee issue.
"Josh had a concussion injury, so you know the rules. He will not be available for the game. He felt really bad the two days after," Clement confirmed.
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"He is starting to feel better now, so that is a positive, but he will not be able to play. There are clear rules in the world of football for how many days you need to watch out [after a concussion]. Those are things you need to follow.
"It is different from in my days when you had a concussion, and the next day they expected you to be on the pitch. It's good for the players.
"The brain is something that is very important, and you cannot take a risk with that. We will follow the rules strictly, like we should be doing."
Scottish midfielder Kenny McLean is another doubt for the hosts ahead of Saturday's 12:30pm kick-off at Carrow Road, and will be assessed tomorrow.