Manchester United's troubled start to the season took another unexpected twist as they lost limply 3-2 at Brighton & Hove Albion on Sunday with manager Jose Mourinho admitting they were punished for making too many mistakes.

Woeful defending led to two Brighton goals in two first-half minutes as 34-year-old Glenn Murray and Shane Duffy outsmarted United's 117 million pound ($149.21 million) back four to demonstrate why manager Jose Mourinho had sought to upgrade it.

Eric Bailly was particularly exposed and, having conceded a needless corner that led to Duffy's first Premier League goal, he blundered in to foul Pascal Gross, who put away the penalty via David de Gea's leg on the stroke of halftime.

Although Romelu Lukaku had earlier reduced the deficit with a trademark header, United looked ill-equipped to mount a comeback and were often second best to the ball.

Paul Pogba's injury-time penalty, after Marouane Fellaini was brought down, made the scoreline closer than the match itself with Mourinho admitting that his side deserved to lose.

"We made big mistakes and were punished," said Mourinho, although he refused to criticise individuals.

"The accumulation of those mistakes, and the fact that they were punished by goals, gave confidence to Brighton and took it away from us."

Brighton's Murray said their 3-1 home win over United last season gave them confidence that could spring another surprise.

"It was all about the balls being played in to me, I got quality support," said the striker.

Mourinho had started with Anthony Martial but the winger, who is reported to be unsettled at the club, made little impact even when Jesse Lingard and Marcus Rashford were brought on at halftime in an attempt to give United more of a threat up front.

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