Jamaal Lascelles and Jonjo Shelvey make it three wins in a row for Newcastle
Newcastle moved up to fourth in the Sky Bet Championship with a 2-0 victory that brought an end to Brighton's six-month unbeaten run.
The Seagulls had not lost in the league, excluding May's play-offs, since February but could not prevent the Magpies from making it three wins in a row to help forget about starting the campaign with two defeats.
Newcastle captain Jamaal Lascelles put Rafael Benitez's side in front after quarter of an hour with a powerful header before Jonjo Shelvey added the crucial second in the 64th minute with a sublime free-kick.
Brighton, whose manager Chris Hughton led Newcastle to promotion in 2010, could find no way back after that having been reduced to 10 men when Sam Baldock was sent off for a second caution in the 55th minute.
Shelvey's first goal for Newcastle since his B#10million move from Swansea in January followed that dismissal and after that Brighton battled but to no avail.
On a day when it was confirmed Newcastle are close to adding aerial strength to the squad by moving for Ipswich's Daryl Murphy, it was ironic that it was a header which put them ahead.
It was not from lone striker Ayoze Perez, asked to lead the line in the absence of Aleksandar Mitrovic and Dwight Gayle, but the more unlikely source of centre-back Lascelles.
The Newcastle skipper rose just inside the 18-yard box to power a brilliant header inside David Stockdale's right-hand post after meeting the fine free-kick delivery of Matt Ritchie.
Brighton, with eight points from four undefeated matches previously this season, looked hungry to impress but the noise levels had been lifted and Newcastle enjoyed the rest of the half.
Yoan Gouffran almost scored a belter of a second nine minutes later. A move that started in the right-back position, where Vurnon Anita made a tackle, ended with a blistering 30-yard drive from Gouffran which crashed off the crossbar.
Newcastle looked confident in possession but still had to be wary of a Brighton side showing glimpses of why they have been hard to beat for so long.
Seconds before Baldock's sending off, the Seagulls almost levelled. Anthony Knockaert, the subject of a failed bid from Newcastle earlier in the summer, cut inside and struck the bar from 12 yards.
But Brighton's task was made harder when Baldock, already cautioned for a foul on Perez, arrived late to wipe out goalkeeper Matz Sels after he cleared his lines and that was enough to earn him a second yellow.
Nine minutes later it was two when Mohamed Diame was brought down by Steve Sidwell 25 yards from goal. Shlevey, back in the side under Benitez, curled a fine free-kick over the wall and inside Stockdale's top-left corner.
Shelvey almost had a second too, but his low strike destined for the bottom corner was turned behind for a corner as Brighton struggled to find a way through to make a game of it.