Former Manchester United forward Dwight Yorke has described the team's performance against PSV Eindhoven in the Champions League as "naive".
Louis van Gaal's side kicked off their campaign in Europe with a 2-1 defeat in Holland on Tuesday night.
Memphis Depay gave United the lead when he scored against his former club in the 41st minute, but goals from Hector Moreno and Luciano Narsingh resulted in a PSV triumph in Group B.
"I think they played well enough to certainly come away with a result," Yorke told Sky Sports News. "I'm sure this will be a massive blow to the United players. To dominate the game for such a long period of time and to not have taken the opportunity and let PSV back into the game, they will be absolutely devastated.
"Call it naive but at this level you cannot afford to make the mistakes they have made and they paid the price. This will probably be a wake-up call. At this level of the competition you need to take your opportunities and they haven't been able to do that.'
United are also expected to be without full-back Luke Shaw for at least six months after he suffered a double leg fracture in the first half.
Danielle Joynson
