Glenn Murray repeated his own feat, as the first player to hit 20 goals for Brighton in a season since 2010-11
Brighton & Hove Albion moved two points clear of Newcastle at the top of the Championship with a routine home win against strugglers Birmingham City.
Glenn Murray's 20th goal of the season put Albion ahead on two minutes, turning in Bruno's cross on the run.
Birmingham frustrated the hosts for the rest of the half, but Tomer Hemed chested in a second early on after the break to ease the pressure.
Uwe Hunemeier's fierce shot made it three, before Che Adam's consolation.
With nearest rivals Newcastle and fellow challengers Huddersfield not in action until Wednesday, the onus was on Brighton to get a confidence-building head-start.
Birmingham, without a win in five but having drawn the past three, saw any plans to hold Brighton blown away as the hosts' slick move teed up Murray for his landmark goal.
However, the Seagulls then seemed to fall back to the irritation of the expectant support while Craig Gardner's set-pieces appeared Birmingham's best hope, particularly when one curling effort brushed the woodwork.
Lewis Dunk's withdrawal through sickness in the first-half added to the concerns, but his team-mates shook off any of their own issues in his absence with two vital strikes shortly after the break.
Hemed's finish, his first in six matches, had The Amex rocking again and when Hunemeier smashed in, it was game over.
A smart move down the right gave Adams a rare opening to beat David Stockdale from inside the box with five minutes to go for a Birmingham consolation.
Brighton have a 10-point cushion to Reading in third with six matches remaining as they look for a return to the top flight for the first time since 1983.
Brighton manager Chris Hughton told BBC Sussex: "It was certainly scrappy, the fact we got the early goal normally motivates a team to go on but then we had a difficult period where we rested on that one goal, and you can't afford to do that against anybody.
"I was agitated in that first half, we needed to be more like ourselves. Fortunately we worked better in that second half and took our moments when we needed to do.
"Glenn is one who will always score, he has a knack, even when he's not playing well he gets in the right place at the right time.
"Our hard work has put us in the position [top of the league] but the last two games have shown us it can go either way. If you're not at the levels, it can go dramatically against you."
Birmingham City boss Gianfranco Zola told BBC WM: "It made the game really tough [conceding after two minutes]. We wanted to be defensively strong and wait for our moment to hit them on the counter, but it was a poor start.
"It was a poor start to the second half as well and it compromised the game. We had some good spells where we deserved our goal in the second half.
"But if you allow a team like Brighton to be in front then it comes difficult with the value of their team."
