The trio are some of the Red Devils’ long-term absentees but will be hoping to make their returns to action before the end of the current campaign.
United are still aiming to progress through to the quarter-finals of the Europa League when they host Liverpool at Old Trafford on Thursday night looking to overturn a 2-0 deficit from the first leg.
The Red Devils are also still in with a chance of FA Cup glory after Anthony Martial’s equaliser rescued a 1-1 draw on Sunday and forced a replay of their quarter-final tie with West Ham.
And Van Gaal believes that the possibility of featuring in a cup final could prove to be perfect motivation for the injured Red Devils.
Van Gaal told United’s website: “I have seen an entertaining match and we are still in three competitions.
“So I said that to Shaw, Rooney and Young, all the players, you can still play in the final.
“It’s very important to still be in the cup because a lot of players are still coming back and now you have seen [Bastian] Schweinsteiger play again for 15 minutes so I have more choices. But I still have to build up a number of players in the coming weeks, which is not so easy.
“I like the way Schweinsteiger came in but he is still not ready for 90 minutes. Of course, [Guillermo] Varela is playing at the moment and Matteo Darmian is not playing. He is doing it very well which is the reason I play him but maybe, next time, Darmian will play.
“There’s fantastic spirit in the team in spite of the very nasty week in a lot of aspects. I’m very proud of my players and the fans are also very proud. They were enthusiastic and applauded when the players were going off the pitch.”
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