Sofiane Boufal’s wonder goal sent Sunderland out of the EFL Cup as Southampton secured a place in the quarter finals.
With little to separate the sides during the opening 60 minutes, the Frenchman plucked the ball out of the air before curling a sumptuous strike past the helpless Jordan Pickford.
Jermain Defoe entered the fray with 20 minutes remaining as David Moyes’ side rallied, Victor Anichebe thought he had won a penalty as he spun Maya Yoshida in the box but the referee waved play on as Moyes was sent to the stands.
Sunderland continued to pile forward but were unable to find a response as their cup campaign came to an end.
The Black Cats made four changes to the side who lined up against West Ham United, with Anichebe making his first start in red and white as Defoe dropped to the bench.
Captain John O’Shea was also named on the bench as Papy Djilobodji came into a starting XI which also included Billy Jones and Paddy McNair.
Lamine Kone captained Sunderland.
Pierre-Emile Hojbjerg mustered the first attempt on goal with four minutes on the clock, but the former Bayern Munich midfielder was denied as the colossal Kone produced an emphatic block.
Summer signing Boufal – making his first start – was next to test the Sunderland defence, but after powering past Djilobodji and spinning past Wahbi Khazri he was thwarted by Patrick van Aanholt.
The home side were forced into a change as the half-hour mark approached as Jay Rodriguez departed following a clash of heads with Jones.
Olufela Olomola replaced the striker to make his Saints debut but the momentum continued to shift as Sunderland grew into the contest.
And chances followed as Khazri almost connected following a fluid move before McNair saw an effort blocked.
A midfield battle soon ensued as both sides struggled to gain the advantage, and there was nothing to separate them at the break as the opening 45 minutes ended goalless.
Like Sunderland, Anichebe grew into the game and his hold-up play improved as time wore on, with the striker doing exceptionally well on 55 minutes to take down the ball and win a free-kick on the edge of the box.
Van Aanholt stepped up and curled his effort over the wall, but also over the crossbar.
Both sides needed inspiration but with 66 minutes played it was Boufal who provided it, taking the ball down with aplomb before lashing it past Pickford on his first start for the club.
Sunderland’s best opportunity fell to substitute Defoe who forced Alex McCarthy into a low stop before Anichebe thought he had won a penalty when he was brought down inside the area by Yoshida.
Strong appeals from the away rang around St Mary's but the referee waved play on as Moyes was dismissed to the stands. From there, Southampton held out as the night belonged to Boufal whose one moment of magic made all the difference.
Southampton: McCarthy, Yoshida, Fonte, Stephens, McQueen, Reed (Clasie 82), Ward-Prowse, Hojbjerg, Boufal, Rodriguez (Olomola 26), Isgrove (Redmond 72).
Subs not used: Austin, Martina, van Dijk, Lewis.
Sunderland: Pickford, Jones, Kone, Djilobodji, van Aanholt, Rodwell, McNair (Pienaar 86), Ndong, Watmore (Gooch 86), Anichebe, Khazri (Defoe 72).
Subs not used: Mika, O’Shea, Manquillo, Love.