Manchester United have been told they will have to choose between the Europa League and FA Cup or finishing in the top four.
Since winning the Carabao Cup, United are winless in three games in the Premier League with an aggregate score of 0-9.
Newcastle on Sunday got their revenge for that Wembley defeat with a thoroughly deserved 2-0 win which sent them above United into third in the league.
And now United must decide what to prioritise during the final weeks of the season: trophies or top four.
"Newcastle have got the momentum and the fans, so they have it all going on," Chris Waddle told BBC Radio 5 Live.
"It's an advantage to Newcastle because Manchester United have eyes in other competitions too. The attitude in this Newcastle squad shows they're on a mission."
He added: "This is going to be a hard run-in for Manchester United. If they want to win other trophies, then it might be that they miss out on the top four."
