Darren Moore felt Rovers needed to be more ruthless at both ends of the pitch after being beaten 2-1 at Plymouth Argyle in Sky Bet League One.
Goals from Luke Jephcott and Joe Edwards put the home side in control, before Fejiri Okenabirhie halved the deficit with 20 minutes to go.
Moore said: “There were some good things and some poor things about our performance and that has cost us dearly.
“It’s a difficult one because we haven’t reached the heights in the previous two games but we’ve still had chances.
“We’re kicking ourselves because despite it not being our best performance we’ve still created enough chances to earn a positive result.”
After a slow start at Home Park, Moore says Rovers needed a little bit more composure in possession.
He added: “We have to get back to what we know best and cut out those lapses in concentration going into the next few matches.
“Both teams turned over possession quite cheaply and myself and Ryan Lowe were both frustrated with that.
“Sometimes you need a little bit more composure on the ball, we showed that at times but not for long enough in the game.”