Barcelona defender Javier Mascherano says they didn't work hard enough in defeat to Champions League opponents PSG.
PSG shocked Barca 3-2 in France last night.
Mascherano said: "You don't deserve wins. You have to achieve them. We didn't start the first half well and we struggled to get into the second. You pay a high price for slight errors in games like these. But we carried on battling in the second half.
"Defeats are always worrying. We need to improve. We could have got a bit more out of it towards the end. But we have to lift our heads up because this hasn't finished yet. We need to correct our mistakes and keep improving."
