Manchester United entertain Everton in the Premier League on Monday night.
Ahead of the encounter, the Red Devils will be without their main centre-forward.
Benjamin Sesko sustained a knee injury against Tottenham Hotspur prior to the international break.
The setback is not deemed serious, but he is expected to miss out against the Toffees.
Speaking at today’s press conference, Amorim said that Sesko will be sidelined for a few weeks.
He added that Sesko should return at the same time as Amad Diallo, Bryan Mbeumo and Noussair Mazraoui report for Africa Cup of Nations (AFCON) duty.
Amorim said: “He is going to stay a few weeks out. I don’t know how long but it is not that serious we have to be careful with him. He is going to recover.
“He is doing the recovery and he is feeling better so we expect in a few weeks to have him back.
“I think it is going to be more or less he will be back at the same time as Amad and Mbeumo leave for AFCON.
“I don’t want to say for sure but when they are going to the camp I expect to have Ben back.”
Amorim said in his presser that the African contingents will need to report for AFCON two weeks prior to the tournament, but the Red Devils are negotiating for a late release.
The trio have to report after December 7, but the club could seek to delay until December 16 such that they are available for the games against Wolverhampton Wanderers and Bournemouth.
Sesko could be available to return to action by then. The Slovenian ace has netted only two league goals since his summer move, and the injury probably came at the wrong time for him.
The ex-RB Leipzig man was starting to find his feet in the Premier League, and now needs to go through the process of building up form and fitness before the second half of the season.
Sesko’s return would be a big boost for United in the final third as Mbeumo and Amad could potentially be away until January 18 if Cameroon and the Ivory Coast were make the AFCON final.
Stats from Transfermarkt.com