Barnsley lead Leicester City after two goals overcame an early Anthony Knockaert opener.
Martyn Waghorn had the first sight of goal after four minutes, but he could not beat Luke Steele despite working the Barnsley goalkeeper.
Four minutes later it was 1-0 to Leicester, with Knockaert curling a lovely finish into the bottom corner.
Barnsley were level on 26 minutes and Kasper Schmeichel was to blame. His pass to Paul Konchesky was cut out and after a scramble in the box Scott Wiseman finished.
It got worse for the hosts as Barnsley made it 2-1 with five minutes to play in the half when Jonathan Greening lobbed into the box for Reuben Noble-Lazarus to finish with a bicycle kick.
