The Old Lady took up the option to sign the former Cagliari star on a permanent basis in the summer of 2011 following a successful six-month loan spell at the club but mustered only 13 more strikes in his next 53 appearances.
However, he recently took advantage of Antonio Conte's rotation policy in attack, despite the recent addition of Nicolas Anelka, and scored his third goal in four matches in last week's 3-0 Champions League victory over Celtic.
"I’m currently in better shape than I was a few months ago, but I’ve always worked hard to improve," he told reporters.
"On the pitch, however, sometimes things go well and other times less so. It’s pleasing to know that certain people are now starting to believe in me again.
"I’ve never thought about leaving Juve, the club has always been right behind me and that’s the only thing that I’ve ever been interested in."Matri then reflected on Juventus' defeat to Roma in Serie A last weekend - their fourth league reverse of the season - and is adamant that the team will demonstrate an improvement against Giuseppe's Iachini's side.
"We all sat down and analysed our performance together. Not much went right for us, the game began badly and ended even worse," the Italy international added.
"We’ve understood the errors we committed and now we’ll set off again with the same desire to win that we’ve always possessed.
"We can’t think about Napoli at present, even if I don’t believe the game at the San Paolo will be decisive as far as the destiny of the title is concerned.
"We’re just thinking about the game against Siena which is currently the most important as far as we’re concerned.
"We know that it represents a complicated fixture, they’re in good shape both mentally and physically, they’ll come here to sit back before looking to break on the counterattack."