Ole Gunnar Solskjaer praised Juan Mata after his man-of-the-match display brightened up a rainswept night at the AmEx.
Manchester United veteran Mata, 32, scored and provided an assist as the visitors reached the quarter finals.
And boss Solskjaer immediately set a target of improving on last season when they lost three semi finals.
The United boss said: “His composure, his experience and his different qualities were so important for us tonight.
“He is a top pro, a fantastic professional and has so much quality.
“He scored a wonderful goal and is so full of determination that he won a free kick against a 6ft defender and then took it and set up a goal.
“He has had a fantastic career, won everything there is to win and is a great example to us all.
“It was a very good win and even at 1-0, Dean Henderson made such an important save and he loves clean sheets.
“It will definitely be a drive for us this season to go further than last year.
“We are already in the quarter finals, this is a job well done and of course the semi final defeats are going to hurt.
“So we have to make sure we can do better this season and that’s the target.”
Brighton boss Graham Potter insisted the scoreline looked harsh on his team as they fought hard before the late rally.
He said: “I’m disappointed because we’ve lost and are out of the competition.
“We had a chance at 1-0, their keeper made a really good save. Rashford and Pogba came on and things get more complicated. 3-0 looks a tough scoreline but there are fine margins.”
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