Jose Mourinho praised Brighton's performance after Manchester United battled to a 1-0 win at Old Trafford this afternoon.
Ashley Young's 66th-minute deflected strike was all that separated the sides and United boss Mourinho said Albion caused United more problems than any other away side so far this season.
It was a tenth successive home win in all competitions for Manchester United but Mourinho said: "It was a battle because Brighton were very good. From minute one until the last minute, I thought they were good.
"They had a good approach, defensively they were well organised. They changed as they normally play (Pascal) Gross as a second striker but today they played a line of five across the midfield.
"I keep saying defending well is very important and they defend very well and then they were quite dangerous on the counter-attack.
"They had a couple of crosses across the face of the goal and I think they played really well.
"We didn't play well. The intensity got higher in the second half in search of the goal and then after the goal we couldn't kill the game but we did everything to keep the clean sheet and I'm happy with the attitude.
"But I have to praise a team and a manager who until a few months ago were playing in the Championship.Today they came to Old Trafford and they were the team until now who have caused us the biggest problems."