Josh Benson struck in the third minute of stoppage time as League One Barnsley claimed a 1-0 win at the Riverside to dump Championship Middlesbrough out of the Carabao Cup.
Benson, who was a second-half substitute, slotted home the rebound after his own shot had been parried by Middlesbrough goalkeeper Liam Roberts.
Middlesbrough should have opened the scoring after just two minutes, but after being sent clear of the Barnsley defence, Duncan Watmore rolled a low shot too close to Tykes goalkeeper Jack Walton, who was able to save with his legs.
Hayden Hackney fired a low first-half effort wide for the hosts, but Barnsley settled after a shaky start and went close themselves when Aiden Marsh wriggled free in the 18-yard box, only for his close-range strike to be saved by Boro debutant Liam Roberts.
Paddy McNair glanced a second-half header wide from a corner, but while Boro spent most of the second half pushing for a winner, substitute Daniel Dodds was denied by a sliding challenge from Robbie Cundy.
Dael Fry had the home side’s best late chance to secure a winner, but his goal-bound header from Caolan Boyd-Munce’s cross was tipped over by Walton.
And just as the game looked to be heading to penalties, Benson struck in injury-time to ensure Barnsley were able to celebrate a cup shock.
