Leganes stunned Barcelona with two goals in 69 seconds to come from behind and hand the champions a first LaLiga defeat of the season.
Quickfire goals from Nabil El Zhar and Real Madrid loanee Oscar Rodriguez stunned Barcelona and handed Leganes a shock 2-1 LaLiga win.
Barca had gone in front through Philippe Coutinho's fine 12th-minute touch and volley and looked in control until the home side struck in quick succession at a boisterous Butarque.
El Zhar set the turnaround in motion with a thumping back-post header soon after half-time and it was Rodriguez who capitalised on Gerard Pique's dreadful error before Barca had been given time to take stock.