'Worried' - Manchester United told key issue they must solve ahead of FA Cup clash with Brighton

Manchester United's defensive frailties should be cause for concern when the Reds take on Brighton in the FA Cup semi-final on Sunday.

Erik ten Hag's side were dismantled 3-0 by Sevilla in the second leg of their Europa League quarter-final on Thursday night to bow out 5-2 on aggregate. It ends the prospect of European glory this term but United remain in contention for a domestic cup double with the Seagulls standing in their way of a place in the Wembley showpiece.

But Roberto De Zerbi's side are enjoying a fine season and are pushing for a top-six finish in the Premier League. Brighton beat United on the opening day of the campaign at Old Trafford and beat Chelsea last time out.

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And former United defender Paul Parker, who won the 1994 FA Cup with the Reds, insists United must be on their game to secure a Wembley win. The former right back sees a vulnerability in Ten Hag's backline, particularly given the ability Brighton have up front.

“It will be a big test for the discipline of that back four,” Parker said. “I worry about them playing against Brighton because if you drop deep against Brighton, you are just saying ‘come and get us’ then they can dominate the midfield.

“United are up against a team in serious and consistent form. Brighton play incredible football. It doesn’t matter what is happening, they do not change, they do not panic. Brighton are better than they were under Graham Potter – and they were good under him. Now they are more progressive, with a little bit more aggression and have added that bit of belief in themselves.

“When they go 1-0 down they don’t fall apart – we saw that (in the Premier League win against Chelsea)