The game got off to a bad start for a lacklustre United, as Andros Townsend got the better of Shaw at the far post to put the Eagles a goal ahead inside seven minutes.
Referee Martin Atkinson used the VAR monitor to award Palace a penalty for a handball by Victor Lindelof. Jordan Ayew missed the initial spot-kick, but it was ordered to be retaken with David de Gea adjudged to have been off his line, and Wilfried Zaha converted the second attempt.
Van de Beek is United’s only major signing of the summer so far, and with their rivals around them strengthening their squads, Shaw made clear that more incomings are needed.
‘We have a very good group, but personally I think we need more players to strengthen the squad,’ the left-back told TV2.
‘It can give us a boost. When you look around at how other teams are strengthening their teams, then we must also do it to keep up with the others.’
Shaw pointed towards the lack of a full pre-season as a reason why United weren’t as sharp as they should’ve been for the start of the new campaign.
‘Possibly everything went wrong. From my point of view, the pre-season that we’ve had is not the correct way it should have been, we’ve had a week all together,’ Shaw told Premier League Productions.
‘We haven’t been able to prepare in the way that we wanted. That’s not an excuse because we have the quality of players to be able to win games like this but we weren’t up to it and we’ve been punished.
‘It’s the start of a new season, we should have been fresh.’