Barcelona captain Carles Puyol has criticised referee Joan Eriksson following Wednesday's goalless draw with AC Milan in the Champions League quarter-finals.
Puyol was denied a penalty in the second half at the San Siro when he looked to have had his shirt pulled by Djamel Mesbah.
Barca could have also had a spot kick earlier in the match when Alexis Sanchez was felled by Milan goalkeeper Christian Abbiati.
"Everyone saw what happened," Puyol told AS. "As I was trying to head the ball, I had my shirt pulled.
"The referee did not want to award us a penalty. I saw it on the screens.
"But we do not have to look for excuses. We have to play. Refereeing is very hard."
The second leg at the Nou Camp takes place on Tuesday.