Fiorentina coach Vincenzo Italiano explained clashing with a fan after defeat to Lech Poznan.
The 3-2 loss at the Stadio Franchi still saw the Viola reach the Europa Conference League semifinals 6-4 on aggregate.
Italiano said: "Fans are often less clear-headed than coaches.
“When there are struggles, one has to remain calm. I argued with a gentleman who has been there for two years. I told him that the important thing was to qualify.
“We played well in the first half, but things became complicated in the second half. We were no longer united as it had happened against Braga. We remained in the game and qualified. Games in Europe are endless, luckily we managed to bounce back."
He added: "When you go 3-0 down, you may fear that something unthinkable will happen. We'll analyse this. Unfortunately, we suffered a defeat, but it was enough to qualify."