England star Dele Alli's 65th-minute strike knocked Barnsley out of the Carabao Cup after a 1-0 loss at Wembley against Tottenham Hotspur in the third round.
Although the Premier League hosts had most of the possession and territory, they struggled to open up a Barnsley side who held their own for the majority of a competitive cup tie and had several excellent chances.
Paul Heckingbottom made five changes to the side which lost to Aston Villa on Saturday as he produced some surprises in his starting 11. Jared Bird made his full senior debut while ex-Spurs left-back Zeki Fryers made his Barnsley debut.
Club captain Angus MacDonald replaced Adam Jackson while Ryan Hedges and Ike Ugbo came in for 2016 Wembley hero Adam Hammill and Tom Bradshaw. Matty Pearson and George Moncur also dropped out.
Spurs also made changes but still started Alli as well as other regular first teamers such as Heung-Min Son, Mousa Dembele and Jan Vertonghen.
It was one of the youngsters who almost gave Spurs the lead in the third minute when centre-back Juan Foyth beat Ugbo in the air and headed narrowly side from a corner by former Barnsley player Kieran Trippier.
The Reds settled into the game and Hedges had a couple of good opportunities to cross into the home box but could not pick out a team-mate. Fernando Llorente headed over when he should have scored from another Trippier corner after his marker Liam Lindsay was blocked off by Foyth.
Barnes was denied by an excellent Vertonghen tackle after appearing to be through on goal in the 32nd minute when he could have set up a tap-in for Brad Potts following a swift Reds counter-attack.
Barnsley then had a superb chance to take the lead when Hedges' right-wing corner found Lindsay unmarked six yards out but the Scottish defender nodded it wide of the far post.
There was an even better chance for the visitors ten seconds after the break when Fryers' long ball found Ugbo on the edge of the box and he dinked the ball over Vertonghen's head to go clean through but shot straight at goalkeeper Michel Vorm.
Alli then shot just wide from 20 yards but, at the other end, Potts blasted over inside the home box after Hedges' cross appeared to hit Trippier's hand but penalty appeals were waved away.
Another right-sided Trippier cross created a fine Spurs chance on 62 minutes when Harry Winks brought the ball down six yards out at the back post but Adam Davies blocked brilliantly with his chest.
Trippier created the goal on 65 minutes when he skipped past debutant Bird on the right side of Barnsley box and slid across a low ball which Alli fired in low from six yards out.
Tottenham substitute Georges-Kevin Nkoudou fired straight at Davies after cutting past Fryers inside the box then Alli shot wide again with a curling shot from the edge of the box.
Heckingbottom made changes and two of his substitutes almost combined to equalise when Hammill's shot hit Bradshaw and trickled narrowly wide. Son then turned Bird on the left of the box but fired straight at Davies from a tight angle.
The Reds seemed to tire late on and could not find the equaliser but should be pleased with their efforts.
