Barcelona were held to a 2-2 draw by Valencia on Saturday and Ronald Koeman acknowledged his side switched off too easily at the back.
Ronald Koeman has put Barcelona's 2-2 draw with Valencia down to a lack of concentration from his players, rather than a problem with their attitude.
Barca were held at Camp Nou in Saturday's entertaining La Liga clash and are now eight points adrift of Atletico Madrid having played a game more than the leaders.
Mouctar Diakhaby scored a free header to give Valencia the lead – a joint-high fourth league goal Barca have conceded from a corner this term along with Huesca – but Lionel Messi equalised and young defender Ronald Araujo put the hosts in front.