Ernesto Valverde said Frenkie de Jong's sending-off hurt Barcelona at a crucial moment in their 2-2 derby draw with Espanyol and noted his side's difficulties in killing off games.
The Blaugrana came from a goal down at RCDE Stadium to lead 2-1 thanks to goals from Luis Suarez and Arturo Vidal but De Jong was shown a second yellow card 15 minutes from time.
It was the midfielder's first career red card in league football and preceded an Espanyol fightback in which Wu Lei scored a deserved equaliser to earn La Liga's bottom club a share of the points.