Tomer Hemed's hooked strike denied Newcastle the chance to move fourth in the Premier League as Brighton prevailed 1-0 at the Amex Stadium.
Hemed's second Premier League goal sealed the Seagulls' triumph and manager Chris Hughton's first win over former club Newcastle at the seventh time of asking.
Brighton moved 13th in the table with their second win of the campaign, hitting back after losing at Bournemouth in first the Premier League then the Carabao Cup this past week.
Israel forward Hemed added to his goal in the 3-1 home win over West Brom to tie up three more priceless points for Brighton, finishing smartly from Dale Stephens' tee-up.
20 - Tomer Hemed has had a hand in 20 goals in his last 23 league starts at the Amex Stadium for Brighton (15 goals, five assists). Source.— OptaJoe (@OptaJoe) September 24, 2017
Newcastle were the only side to do the double over Brighton in the Championship last season, but the Seagulls exacted some revenge on the south coast in edging out the in-form visitors.
Rafael Benitez's men arrived at the Amex boasting three straight league wins, but paid the price for Joselu's glaring first-half miss in drawing a blank in front of goal.
The £5million summer recruit from Stoke fluffed his lines at the key moment, hacking wide when presented with a clear opening at point-blank range.
The high hopes raised by Joselu's first Newcastle goal in the 3-0 home win over West Ham back in August have slipped somewhat, with the 27-year-old now boasting just that solitary strike in five Premier League outings.
Pascal Gross wound up scratching his head as to how he had not handed Brighton the advantage earlier, after his effort was deflected wide by team-mate Anthony Knockaert.
Mathew Ryan batted away Mikel Merino's volley to open proceedings, before Newcastle cleared the danger from a six-yard box scramble.
After Joselu missed his sitter, Christian Atsu's teasing low cross was made for Ayoze Perez to turn goalwards, but the visiting forward was unable to make contact.
Brighton had the last half-chance of the opening period but Shane Duffy's flicked header straying just out of Hemed's reach.
Straight after the break Brighton capitalised on another free-kick to steal the lead, Stephens nodding across goal for Hemed to hook into the roof of the net.
The ex-Almeria forward's smart finish had Brighton all fired up, and only moments later Rob Elliot had to block Solly March's effort from an acute angle.
Newcastle kept pressing throughout the second half but failed to make any dominance count.
Substitute Jonjo Shelvey called for a penalty after a tussle with Brighton skipper Bruno, but those protests were waved away by referee Andre Marriner.
Brighton's nerves grew as Newcastle kept nipping at their heels well into the final moments, but the Seagulls held firm to secure victory.