Manchester United boss Jose Mourinho believes his side felt "mental pressure" in their 3-1 defeat to Manchester City on Sunday.
Goals from David Silva, Sergio Aguero and Ilkay Gundogan gave the Sky Blues the win at the Etihad Stadium, with United's only reply coming from Anthony Martial via the penalty spot.
It was the Red Devils' second important away game in the space of five days, and Mourinho believes that took a toll on his players, per the Daily Mail's Chris Wheeler:
"Everybody has to agree, it is one thing to go to Juventus and play against one of the best teams in the world for 90 minutes—a game that demanded everything we had to give not just physically but also mentally—and another thing to beat Shakhtar Donetsk at home 6-0 and be very relaxed.