Rashford missed training on Tuesday after picking up a knock in the win over Brighton but is OK to play in attack.
Goalkeeper Dean Henderson, who started in place of David de Gea for a seventh straight game against Brighton, is on the bench with De Gea given a chance.
"I cannot prioritise the league or Europa League. The next game is the most important one," he said.
"David has been a top keeper and is still a top keeper. I'm comfortable playing David or Dean and pleased that either of them are happy to be a sub."
Solskjaer also said Anthony Martial had begun his recovery after sustaining a knee injury on international duty, but is unlikely to feature over the rest of the season.
"If we see him before end of season I'll be very surprised," he said. "He wants to get back as quick as possible."
Man Utd XI: De Gea; Wan-Bissaka, Lindelof, Maguire, Shaw; Pogba, McTominay; James, Bruno Fernandes, Rashford; Greenwood
Subs: Grant, Henderson, Cavani, Mata, Fred, Amad, Alex Telles, Matic, Williams, Van de Beek, Tuanzebe, Elanga
Manchester United's travelling squad
Goalkeepers: David de Gea, Dean Henderson, Lee Grant, Nathan Bishop.
Defenders: Victor Lindelof, Harry Maguire, Luke Shaw, Alex Telles, Axel Tuanzebe, Aaron Wan-Bissaka, Brandon Williams.
Midfielders: Amad, Bruno Fernandes, Fred, Daniel James, Juan Mata, Nemanja Matic, Scott McTominay, Paul Pogba, Donny van de Beek.
Forwards: Edinson Cavani, Anthony Elanga, Mason Greenwood, Marcus Rashford.