Dele Alli's second-half strike prevented a shock at Wembley as Tottenham were made to earn a 1-0 win over Barnsley in the EFL Cup third round.
Mauricio Pochettino retained five of his XI from the weekend as he handed first starts to Fernando Llorente and teenage defender Juan Foyth.
And Llorente should have broken the deadlock after half an hour when he headed over from Kieran Trippier's corner, while Liam Lindsay also failed to get a close-range header on target with Barnsley's best chance of the opening period.
Chelsea loanee Ike Ugbo regularly threatened as the Tykes grew in confidence after the restart, but the Premier League side's class eventually told when Trippier got away down the right and put the opening goal on a platter for Alli.
Pochettino introduced Eric Dier to help the safeguard result with just over 10 minutes remaining as Spurs booked their place in the final 16.