And manager Ole Gunnar Solskjaer is not expecting De Gea to be fit after the United goalkeeper suffered a groin injury on global duty with Spain on Tuesday night.
De Gea initially felt the injury during the first half of Spain's Euro 2020 qualifier against Sweden but after being assessed at half-time, the United number one made a decision to continue.
Paul Pogba is also struggling with a foot injury but there is some positive news for Manchester United as Anthony Martial is expected to return from a thigh problem while Aaron Wan-Bissaka has recovered from tonsillitis.
"David needs a scan", United manager Ole Gunnar Solskjaer told Sky Sports.
And the home side continued with that momentum going into the second half, opening the scoring in the 50th minute through Berg, who tipped a header in from one yard after David de Gea (who had to come off around the hour mark with a groin injury) did all he could to make a double save to deny the initial close range attempts from Berg and Forsberg.
"I think he'll be out." he said. He came back and played a couple of games, maybe played through the pain barrier.
Some people might say that, with the injury of De Gea, United's chances of winning have gone from slight to zero. "It certainly looked like it anyway judging on last night, so it's just one of those things", Solskjaer added.
The two injuries are a blow for Solskjaer's side, who sit 12th in the Premier League, 15 points behind leaders Liverpool, who have won all eight of their league matches thus far.