Marcos Rojo is set to play again before the end of the year after Manchester United manager Louis van Gaal said he expects him to return in "less than six weeks."
Rojo, 24, was stretchered off in the second half of United's derby defeat to Manchester City on Sunday, requiring oxygen after injuring himself in a challenge with Argentina teammate Martin Demichelis.
And while the former Sporting Lisbon player's father said his son would only be out for two or three games, there were fears he could be sidelined for up to three months.
Louis van Gaal reveals @MarcosRojo5 dislocated his shoulder vs City but hopes to have the defender back within six weeks. #mufc
- Manchester United (@ManUtd) November 7, 2014
But Van Gaal said in a news conference: "Marcos dislocated his shoulder but did it in positive way. We don't need to operate on him, which is a relief, but maybe with this injury it is very difficult that it shall not happen again.
"That is the problem. Yesterday [Thursday] evening, he saw a specialist who said the conserve way to heal is best. For him, it was positive. Always with these injuries, I cannot change the human body -- God made it, not me. Conservatively, [he faces] less than six weeks out."
United will be without four centre-backs against Crystal Palace on Saturday, with Rojo, Phil Jones and Jonny Evans all injured, while Chris Smalling is suspended after being sent off against City.
Michael Carrick, Paddy McNair and Tyler Blackett are all candidates to fill in, and Van Gaal said: "Smalling is suspended, Evans and Jones are still injured, so I have to solve a problem. I don't want to say who is playing yet. If I say that [what United have done in training] then I give away what I'm trying to do. We've trained today but I may do things differently."
Van Gaal also said that Radamel Falcao, who has missed United's last three games, remains sidelined with injury.
He added: "The problem for Falcao is because of balance in the game. I had to change, he came in and assisted a goal. Then in training he was injured.
"I cannot judge now because he is injured and I changed him not because of his performance but because of the balance of the team, which is much more important than the individual."