Roared on by a sea of fans clad in black and white, Newcastle took complete control of the match seven minutes after the break when Swedish forward Isak swept a shot past Liverpool keeper Caoimhin Kelleher.
Newcastle, who have beaten Arsenal three times this season, will face Liverpool or Tottenham in the final at Wembley on March 16.
Slot was furious that Bergvall avoided a second booking after tripping Kostas Tsimikas with a sliding tackle.
At the Emirates Stadium, Brazilian striker Jesus finally found the back of the net on home turf for the first time in 2024.
Sterling marked his maiden Arsenal start following his transfer deadline day move from Chelsea with a second-half strike in the third-round tie at the Emirates Stadium.
Rodri's absence could mean a more prominent role for Matheus Nunes and the Portugal international blasted in his first goal since joining City for £53 million a year ago.
Ten Hag steered United to the trophy during his first season at Old Trafford in 2022/23 before adding the FA Cup last term, defeating Manchester City in the final following a disappointing campaign in the Premier League where United finished eighth -- a mammoth 31 points adrift of local rivals and champions City.
Paraguay's Matias Rojas opened the scoring in the ninth minute and Uruguayan striker Luis Suarez added an insurance goal in the 72nd minute to deliver Inter Miami's triumph.
Liverpool will face Chelsea in the League Cup final after surviving a scare in their 1-1 draw against Fulham in the semi-final second leg on Wednesday.
Curtis Jones and Cody Gakpo scored three minutes apart as Liverpool fought back from a goal down to beat Fulham 2-1 in the first leg of their League Cup semi-final at a chilly Anfield on Wednesday.
The 21-year-old Hackney's silky finish from an Isaiah Jones pass stunned the visitors in the 37th minute at the Riverside Stadium and the hosts defended superbly to take a slender advantage to Stamford Bridge.
Curtis Jones scored twice and Dominik Szoboszlai, Cody Gakpo and Mohamed Salah were also on the scoresheet for Jurgen Klopp's dominant team, who were trophyless last season.
Manchester United manager Erik ten Hag looked shell-shocked as his team were booed off the pitch and the Dutchman is under intense pressure following their 3-0 defeat by Manchester City at Old Trafford on Sunday.
A Ben White own goal put the home side in front before strikes from Mohammed Kudus and Jarrod Bowen early in the second period put the tie beyond doubt.
Alexander Isak scored the only goal at St. James' Park in a clash between two much-changed sides.
United boss Erik ten Hag and his players have been under fire after a disappointing start to the season.
As Erik ten Hag danced a jubilant jig on the Wembley pitch after Manchester United's League Cup final victory over Newcastle, it was clear the manager's romantic ideas about the club had blossomed into a full-blown love affair.
United hope the showpiece at Wembley can serve as a long-awaited rebirth while Newcastle believe the final can serve as concrete proof they are now a force to be reckoned with.
United are aiming to end a six-year wait for silverware against Newcastle, who are into the League Cup final for the first time in 47 years
