Diogo Dalot has bemoaned Manchester United's lack of 'aggression' in their opening weekend defeat to Brighton in the Premier League.
United fell 2-0 behind to the Seagulls on Erik ten Hag's league debut as manager after a quickfire double from Pascal Gross in the first half.
The Old Trafford side pulled a goal back midway through the second period via an Alexis Mac Allister own goal, but they were unable to find a leveller despite Cristiano Ronaldo's introduction in the 52nd minute.
And Dalot believes his side's lack of aggression without the ball allowed Brighton to build a head of steam.
"We let them play freely a couple of times and they play in behind," the defender told MUTV. "We could stop those counterattacks with a little bit more aggression.
"Like I said we did better in the second half, we kept more of the ball, we had a few more chances but not enough.
"We need to analyse what we did, and what we didn't do right and try to improve for the next game."
The Portuguese was pleased with the reaction from his side after the interval, but he admitted it was too little, too late in the context of the game.
He added: "I think everyone felt that today was a disappointing result, we had a really bad first 45 minutes.
"Second half we got a little bit better but it's still not enough to win a game like this, we knew it was going to be tough.
"There is disappointment but we need to keep our heads up and start working for the next game."