Everton were thumped 3-0 in the Europa League on Thursday night.
The Toffees got their Europa League campaign off to a shocker in Italy, with goals from Andrea Masiello, Alejandro Gomez and Bryan Cristante doing the damage in a first-half blitz for Ronald Koeman's side last night.
The Croatian winger, an £8 million signing from Hajduk Split on deadline day, was given a first start for Everton, but he failed to make a major contribution.
Nevertheless, Koeman singled him out for praise in his post-match interview, but Vlasic himself pays little heed to what his manager has said, admitting that he "could do so much better".
He told the club's official website: "When you lose 3-0, however you play is not enough. I am not satisfied, I think I could do so much better and I believe I will do so in the future.
“It is really good when the manager believes in you. I am happy about that but this is just my first start. I will be better and I will grow game by game.
“Everton fans can expect a lot from me. I want to repay the faith the manager, the Club and the fans have given me, and show them that they did the right thing bringing me to Everton.”
It has been a testing last week for Everton, who also suffered a 3-0 defeat at Goodison Park last week when Tottenham doled out something of a lesson.
But Koeman spent in excess of £150 million in a summer which saw over 10 players join the club and they were always going to encounter problems with gelling early. Sooner they do, the sooner the fans can look forward to what can still be a successful season.