Marco Borriello still feels Roma can improve despite last night's 3-2 win over Fiorentina at the Olimpico.
The Giallorossi went 2-0 up, but kept letting their opponents back in the game, leading to a nervy finish.
"We are too wasteful, me included," Borriello admitted.
"We have to become merciless. Ranieri is right.
"He is a great motivator. We managed to find ourselves again against Brescia. It's there that our season started.
"Now we must get ready for Juventus. We are motivated. We can do it," he concluded.
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