The build-up to the match was overshadowed by ongoing speculation that Everton defender John Stones, a former Barnsley player, would be leaving the Merseysiders for Premier League champions Chelsea after reportedly handing in a transfer request.
Everton manager Roberto Martinez played Stones against his old club despite the transfer hype but the way in which the Toffees were made to struggle by third-tier Barnsley at Oakwell is unlikely to strengthen his resolve to stay with the Toffees.
“I thought Barnsley were superb throughout — dynamic and clinical,” Martinez told Sky Sports.
“We were a little slow in the first half and showed poor focus in front of goal. It was a test to see if we could come back into the scoreline, but it was terrific to see the younger players showing up after a performance that was not acceptable in the first half.
“They reacted with desire in the second half and that shows how much this matters and how much we wanted to progress.”
Martinez added: “I thought that John Stones was incredible under enormous pressure. I think that the authorities need to look at what has gone on because it has become a bit of a circus.
“Our fans know that all we are doing is trying to become better and John is a massive part of that. Money cannot buy everything in life, there are some things like values. He is not for sale.”
Sam Winnall’s shot gave Barnsley the lead before Marley Watkins got on the end of a ball into a crowded penalty area to make it 2-0 in the 28th minute.
Kevin Mirallas and Gary Naismith got Everton back on level terms only for Dan Crawley to make it 3-2 on the hiour mark to Barnsley — a minute after the Toffees’ equaliser.
But Romelu Lukaku made it 3-3 to send the match into extra-time where the unlucky Marc Roberts put a cross from Gerard Deulofeu into his own net before Lukaku made the game safe as Barnsley pressed for an equaliser.
Everton will be away to second-tier Championship side Reading in the third round next month.