The Italian international is wanted by the newly promoted Viola, who were hoping that Boro would allow him to leave on loan.
However, Maccarone has insisted he plans to stay and fight for his place at The Riverside Stadium - despite the recent arrivals of Mark Viduka and Jimmy Floyd Hasselbaink.
"I want to stay with Middlesbrough. I said last year that if I don't play then it's better I go, but if I'm involved then I'm happy," said Maccarone.
"This will be my third season in England and I'm growing in confidence and getting more experienced.
"I want to play because over the last two seasons I didn't do as well as I'd hoped and I want to do better."
Middlesbrough chief executive Keith Lamb insisted on Friday that there was no truth in the rumours of Maccarone departure.
One deal Fiorentina look set to seal is that of Enzo Maresca.
The Juventus midfielder had looked like rejecting a move to the Artemio Franchi, but he has had a rethink and should sign within the next few days.
"I am happy to go to Fiorentina," he said.
