Lazio coach Maurizio Sarri was left angry after their 4-2 Europa League defeat of Feyenoord.
Matias Vecino struck twice on the night for Lazio, which had one stage were 4-0 ahead.
Sarri later said, "In Europe the matches are all difficult. Foreign teams have a different mentality from ours. We gave up on 4-0 up, they don't, so we didn't have to stop. The first 60 minutes were excellent, the remaining too bad because we joked.
"At mentality level we have room for improvement. Today we were extraordinary in the approach, but then we joked and in Europa League this cannot be done.
"Even in Serie A, we collected less than we deserved, we had more scoring chances than other teams. A bit by ourselves, a bit by chance."