The 6'5" striker returned to Florence on transfer deadline day, five years since leaving for Bayern Munich.
He has found the net three times in nine appearances this season, including one on his return against Catania.
However, at 35 and with his contract expiring this summer, the Italian international knows that his playing days are numbered.
"I know that Fiorentina will be my last team, but I don't know whether this will be my last season," Football Italia quotes Toni as saying.
"I know that Fiorentina had other targets before me, but when I was given the opportunity to join again, I opted to put myself on the line in a city which loved me and where I feel at home.
"That's why I feel that I always have to give something more to Fiorentina."
Toni has won 47 caps for Italy.