Albion head coach Graham Potter offered no excuses following their disappointing 1-0 home loss to Sheffield United at the Amex Stadium.
Brighton were second best for the majority of the match and looked extremely vulnerable in defence against a United side who are unbeaten away from home this season.
Oliver McBurnie, who played for Potter at Swansea last season, is United's record signing and scored his third goal of the season to seal the victory for the visitors
"If we think we are just going to turn up at the Amex and start passing through teams then that's a concern," said Potter. "We weren't good. Sheffield United did what they did well. First half they were better than us and deservedly it was 1-0.
"It wasn't a game of many chances and we put a lot into it, but not enough. It was a disappointing day for us. We didn't play well today. They made it difficult for us and we weren't as good as we like to be. We can look at ourselves and learn from the game, we can do better.
"We had the change the dynamic of the game at 1-0 down. Second half it was better in terms of pressure but not enough in terms of chances. You get set-backs in this competition, but we have to get ourselves ready for another tough match."
Wilder's men move up to fifth in the Premier League while Brighton are 13th on 20 points from 18 matches.
Wilder said, "We weren't at our best with the ball but we have a structure, organisation and a desire to keep the ball out of the net. We had to show all those qualities this afternoon.
"We did a job on them, should have had more possession, but we had the better chances on the counter attack and we're delighted to keep the away run going. The next two are Manchester City and Liverpool!
"We kept our shape well and were really disciplined. It's a big three points for us. You always want to get off to a good start.
"It's the Premier League, every team you come across are good and have qualities but we have some qualities as well and we've worked very hard."