Mauricio Pellegrino has confirmed that Mario Lemina will miss Southampton's trip to Brighton & Hove Albion on Sunday.
The midfielder, who joined Saints from Juventus in the summer, suffered an ankle injury in training this week.
Southampton are still waiting to find out the extent of the problem but this will not be done until next week at the earliest, according to Pellegrino.
"I don't know how long he is injured for. He has an ankle injury. We have to wait for the next week and hopefully he can come back as soon as possible," the Argentine told reporters.
"It's a profile of player that we didn't have in the squad. For this reason, we brought him, but we have players to replace him, maybe in a different way.
"When we lose the ball attacking in the final third, we improve a lot in the transition with Mario on the pitch. But every player has different qualities."
Lemina has made seven appearances for Southampton since his £18.1m move from Juve.
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