The 50-year-old Biancocelesti coach admits his side hasn't been ruthless enough in a lot of games so far this season, but mainly attributes its stuttering form to misfortune.
The 50-year-old Bosnian has been under pressure of late because of the Biancocelesti's inconsistent start to the season, with the capital club currently in seventh place in Serie A.
Despite this, Petkovic doesn't feel his side has had the best fortune in a number of games and hopes things will change for the better in Thursday's Europa League meeting with Apollon Limassol.
“Against the likes of Fiorentina, Atalanta and Genoa we’ve just hit some bad luck," the Lazio boss told reporters. “It’s normal to ask for more from your players, but in some cases our efforts have not been repaid. Sometimes we have come unstuck after dominating. Then, our mistakes have been punished.
Without using bad bounces as motivation, Petkovic warned, things will continue trending in the same direction.
“We have to use these results as a wake-up call," he said. "Tomorrow we want to win. I trust that my players will have the same appetite as me. I do not deny that we can improve. We are all involved in this, and we need to find a solution."
Petkovic also bemoaned the way in which his squad has been stretched to breaking point by injuries to so many key personnel, suggesting the club's medical and fitness staff may be doing something wrong in terms of treatment and training.
“Bruises or smaller problems can be avoided," he said. "And we have to analyse why we’re getting so many muscular injuries."