Lyon coach Bruno Genesio was saddened and disappointed by clashes between his club's fans and Besiktas supporters before their Europa League clash.
Kick-off for the first leg of the quarter-final in France was delayed by around 45 minutes after ugly scenes and clashes between fans on Thursday.
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Genesio, whose team went on to claim a come-from-behind 2-1 win, said he was upset to see the violence.
"I'm a little bit upset by what's happening right now, from what happened before the game, because it does not relate at all to the idea of what I feel about sport and football in particular," he said.
"I believe that it must be above all a place where people must be able to come in peace to attend a game, a show.
"And, when we see those kinds of moments, we can only be a little disappointed, sad, sorry.
"After that, I think it is a good thing that the match still went ahead, and we were able to prepare under normal conditions."
The second leg will be played in Turkey on April 20.