DERBY County lead Brighton 1-0 - and 3-1 on aggregate - at half-time in their Championship play-off semi-final second leg at the iPro Stadium.
Will Hughes, in for the injured Craig Bryson, scored after 34 minutes to send the Rams a step closer to Wembley.
Derby made a steady start as they looked to maintain the lead they held from Thursday's first leg on the south coast.
And Steve McClaren's men had the better of the early exchanges.
After 17 minutes, Hughes, Chris Martin and Jeff Hendrick combined to find Andre Wisdom on the right and the full-back cut inside before forcing Tomasz Kuszczak into a low save from 20 yards.
Six minutes later, Martin and Jamie Ward linked up to feed the advancing Craig Forsyth, whose first-time shot from the edge of the box brushed the side-netting.
Derby took the lead when Ward, on the left, laid back to Forsyth and his low cross was turned in neatly by England Under-21 international Hughes from 12 yards out.
It could have been two, in bizarre style, after 42 minutes, when Ward charged down Kuszczak's kick from a backpass and the ball looped narrowly over the bar.
Brighton's best chance of the half came in the 44th minute.
Rohan Ince's neat chip into the area found Leo Ulloa, who controlled the ball before seeing his shot from eight yards blocked well by Lee Grant.
