Born in Asolo, in the Province of Treviso, Veneto, Fietta was a youth product of Treviso Football Club. He won the promotion to Serie B in 2003. However Treviso loaned Fietta back to lower divisions, for Serie C2 club Ivrea. Fietta returned to Treviso in 2004, which he briefly played in 2004–05 Serie B season. In 2005, he left the club again, for Serie C1 club Pizzighettone in co-ownership deal. Treviso also relegated in 2005–06 Serie A season. in June 2006 Pizzighettone purchased Fietta outright for undisclosed fee, however in July 2006 Treviso bought Fietta back for €45,000. That season he made 24 Serie B appearances. In July 2007, Fietta, Marco Zaninelli and Alfonso Camorani were signed by fellow Serie B club Spezia in temporary deal.