NEIL Harris believes The Den will be "rocking" this Sunday – especially after Millwall's superb 2-0 win at Birmingham City on Wednesday night.
While the Lions haven't moved further away from the relegation places owing to Rotherham's victory at QPR, Ben Thompson's brilliant double has lifted the mood after four straight league defeats ahead of the visit of Brighton to south London for a battle for a place in the FA Cup semi-finals.
Millwall's next league game is at Leeds after the international break, when they could be in the bottom three depending on other Championship results this weekend as they focus on making more history in a competition they were last in the semi-finals of in 2013.
Harris said that whatever the result would have been at Birmingham his players would have been looking forward to their tilt at reaching the last four.
"This game would have been swept aside no matter what, everyone would have separated from this game and looked forward to the weekend," Harris said.
"The Den will be rocking at the weekend, even more so now on the back of tonight, everyone will be more vibrant and positive.
"The players can, not relax and enjoy it because they'll enjoy it anyway, but I think this puts us in a good place for the next two-and-a-half weeks.
"We can't control what happens Saturday in the league with the teams around us. What we can do is focus on Sunday and really enjoy it and know that when we come back to play Leeds away that we'll be going there on the back of that performance."
Seagulls boss Chris Hughton was at St Andrew's on Wednesday to watch the weekend's opponents.
Harris was asked what Hughton would have learned about Millwall.
Harris replied: "If he had any doubts that we weren't a team that's going to dig in and have a right go on Sunday, he's seen that tonight and he'll have known that anyway.
"Free game for us Sunday, would I look at it like that? Possibly, because a Premier League team should come and beat us.
"Quarter-final of the FA Cup, they'll look at it and their fans will look at it and think what an opportunity for them. We've achieved already by getting to the quarter-final. My lads will just go and enjoy it.
"Chris and his boys will know they're in for a tough game at the weekend.
"It's going to be a great atmosphere at The Den, Millwall-Brighton, Sunday afternoon. It doesn't get much better than that. It certainly doesn't get much better than that for my group of players.
"It's never a free game in football, but there's no pressure on us. That was how we took the Everton game, and we performed in that.
"We know about it ourselves, we went to Wimbledon and there was huge expectation for us to go and win there. The players handled it really well.
"Brighton have experienced players and certainly a top manager. They'll come to want to beat us, but we'll enjoy it and what I do know is my players will have a right go because they want to be in the semi-final."
Image: Millwall FC