Southampton manager Ronald Koeman was left ruing his side's mistakes following their 3-2 defeat to Manchester United in the Premier League.
The Dutchman praised his players for their positive start to the match, but claims that they "lost belief" shortly after taking the lead through Graziano Pelle.
"The first 30 minutes we played perfectly, we had good organisation and they had difficulties breaking us. We lost it a bit 10 minutes before half time. In the second half, if you make that kind of mistake it is impossible," he told Sky Sports News.
"We lost belief. The reaction after 3-2 was good and we had enough chances but David de Gea made some good saves. We didn't lose by Manchester United, we lost by ourselves.
"We can play good football when we have control. It is all about belief. Making mistakes is a part of football but we have to continue. There have been a lot of changes in the game but we are still strong."
An Anthony Martial double and a Juan Mata strike put United into a 3-1 lead before Pelle struck again to reduce the deficit five minutes from time.