Shea Charles fired the Saints on their way to Wembley with a curled left-footed shot that bounced in off the inside of the post in the 116th minute after the 90 minutes ended 1-1.

Hull beat Millwall 2-0 in the other playoff semi-final in London on Monday.

The final, dubbed the “richest game in football” because of the huge financial rewards of playing in the top flight, will be on May 23.

After a goalless first leg and still deadlocked in the second, the sides headed into extra time still with everything to play for and Southampton’s St Mary’s stadium crackling with tension.

Riley McGree stunned the home crowd when he fired ‘Boro ahead after five minutes with a side-footed shot low into the corner.

Ross Stewart missed a good chance to equalise seven minutes later but the Scot made up for the miss with a header just before the break after goalkeeper Sol Brynn parried a Ryan Manning effort.

Tempers flared on the touchline before that with Middlesbrough manager Kim Hellberg and Southampton’s Tonda Eckert having to be physically separated as referee Andy Madley had a word.

Sky Sports television said Boro defender Luke Ayling had earlier reported Southampton’s Taylor Harwood-Bellis to Madley for using “discriminatory language”.

Emotions were already running high after Middlesbrough accused Southampton, who were relegated from the top flight in 2025, of spying on their training before the first leg at the Riverside Stadium.

Southampton, who finished the season fourth in the standings with Middlesbrough fifth, were charged by the English Football League on Friday with an independent disciplinary commission hearing still pending.