Joelinton fired Newcastle a step closer to Wembley with the winner in an action-packed League Cup semi-final first leg success at Southampton.
The Brazilian, who also saw a disallowed goal and was guilty of a bad miss, secured a 1-0 win for the Magpies by burying a low cross from substitute Alexander Isak with 17 minutes to go on a breathless evening at St Mary’s.
Saints thought they had swiftly levelled through Newcastle academy graduate Adam Armstrong but his bundled effort was ruled out for handball following VAR intervention.
Southampton finished a frantic encounter with 10 men after defender Duje Caleta-Car was dismissed four minutes from time for a second bookable offence.
"We controlled the game but we missed big chances," Newcastle's Bruno Guimaraes told Sky Sports.
"It's just the first game now we need to think about the next one. I'm proud of the team today.
"One goal is important, we could score more but most important was to be one-goal in front.
"I want to thank Nick Pope I think he's the best goalkeeper in the world."
The hosts had sufficient chances to head to the north-east level but Pope was inspired to stop Che Adams, in addition to Armstrong’s disappointment against his boyhood side.
Newcastle can now book their long-awaited trip to Wembley in the second leg at St James' Park on January 31, with the winners facing Manchester United or Nottingham Forest in the final.
The Magpies are enjoying a renaissance this season thanks to Howe's astute leadership and the financial investment of the club's Saudi-backed ownership group, sitting third in the Premier League and making their first domestic semi-final appearance since 2005.
Joe Willock should have put Newcastle ahead inside two minutes when he fired wildly over after Miguel Almiron's pass found the unmarked midfielder in the Southampton penalty area.
Willock fluffed his lines again with a wayward volley after Kieran Trippier's pin-point cross picked him out at the far post.
When Willock finally got a shot on target, Saints keeper Gavin Bazunu made the save, with Joelinton's close-range finish from the rebound disallowed for handball.
Carlos Alcaraz was making his first Southampton start since signing from Racing Club and the midfielder forced a save from Nick Pope with a long-range strike.
Teed up by Almiron's raid down the left flank, Sean Longstaff blazed over from the edge of the area early in the second half.
Joelinton fared even worse when Almiron presented him with a glorious chance, somehow shooting over from six yards.
Newcastle finally took the lead in the 73rd minute when substitute Alexander Isak accelerated away from Caleta-Car for a low cross that Joelinton smashed home from close-range to the delight of thousands of Newcastle fans behind the goal.
Southampton thought they had equalised just two minutes later, but Armstrong's finish from inside the six-yard box was disallowed for his handball.
Southampton's frustration was clear and Caleta-Car was shown a second yellow card in the 86th minute.