Manchester United boss Erik ten Hag admits there's disappointment with the manner of Sunday's 1-0 defeat at West Ham United.
David de Gea's failure to make a routine save from Said Benrahma's matchwinning drive produced the only goal of the game.
Ten Hag reflected: "Of course, we are really disappointed, as you see. So the game, I think we started well. I think in the first half we played well and we created good opportunities. We hit twice the post, we had many more opportunities and then one mistake it was a turnaround in the game. And then you're following effects. And the second half we couldn't bounce back.
I think we all know, David knows also, it's a mistake, but he's a brilliant goalkeeper. We may not be in this position when he didn't show this shape over the course of the season. Mistakes are part of football and we have to live with it and we have to bounce back as a team.
Of course, disappointed [not to score]. We created and we had the game in our hands. In front of the goal, we had to be more clinical. I counted four or five really good chances and it was not by coincidence. They were well played.
We have to keep going and we have to show character. It is only four games and you need the energy. It is in your head, make sure it is not in your legs. Get ready for the games, clear head, energy, focus, and go.
I said to the players: 'Don't feel sorry for ourselves.' We want to be in the Champions League, the Champions League is our life, and then you have to suffer and you have to sacrifice and, especially, you have to believe.
"As I just said in the dressing room... come on, it [mistakes] can happen, in this season we've had some terrible setbacks and every time we bounced back so, once again, show the character and go on."