Liverpool manager Jurgen Klopp claims Sadio Mane's hamstring injury is a "concern" after admitting the next few days will be "critical" in the forward's recovery to full fitness.
The 25-year-old suffered a hamstring injury during the last international break. He returned to action in the Reds' 4-1 win over West Ham United on 4 November. Mane was included in the Senegal squad for the ongoing international break.
Senegal sealed a berth in the next summer's World Cup in Russia following their 2-0 win over South Africa on 10 November. Mane played the full 90 minutes as his country made it to the World Cup for the first time in 16 years.
Following their latest victory over South Africa, Senegal confirmed Mane will return to Merseyside after the slight recurrence of "his old injury." The African star will arrive in Liverpool on Tuesday and continue his recovery.
The former Borussia Dortmund manager stressed the Reds medical staff have to be careful and confirmed Liverpool will assess Mane once he returns to the club.
"Specifically on him returning to Melwood early to be with us; obviously it is a concern that the hamstring injury is again on the agenda and it will be critical for us to monitor and manage that in the coming days," Klopp told Liverpool's official website.
"At this stage we haven't seen Sadio yet to properly assess the extent, but what is clear is that we will have to stay on top of this for the rest of the week and make sure we are careful in how we look after him.
"There has been really strong communication between ourselves and the Senegal team management to ensure the player is properly protected and looked after. We respect how important he is for Senegal and therefore it must always be the case that they get to make the decision when he is under their care.
"It should not be forgotten in Liverpool, either, how important it is to Sadio that he represents his country whenever he is fit enough to do so. He is so proud of his country and recognises what a role model he is for them.
"So, in this moment all I can really say with certainty is that we will assess Sadio as soon as he lands back in the country and make decisions on what rehab and treatment gives him the best chance of being back fit and strong for the important fixtures we have coming."
Liverpool host Southampton in the Premier League clash at Anfield. It will be the first fixture after the calendar year's last international break. The Liverpool Echo reports Mane will be doubtful to face his former club on 18 November.