The Italy international started off the season at a phenomenal rate, scoring 16 goals in Fiorentina's opening 13 Serie A matches.

In the three games since, however, he has failed to score, hitting the post and the bar in a 2-1 defeat to Juventus, missing a penalty in a 1-0 win over Treviso and then hitting the post again in a 1-1 draw with Empoli on Sunday.

In Italy the number 17 is considered unlucky, just as 13 is in England and the United States.

"I admit it: I'm starting to believe in the curse of the 17th goal," Toni was quoted as saying in La Gazzetta dello Sport on Tuesday. "I'm a fairly superstitious person."

But the numerical barrier was only half the problem, he said.

Toni has also lost his lucky charm -- a small red horn that usually hangs from the rear view mirror of his car.

"The horn isn't there any more," he said. "I broke it. Or rather I lost the bit you need to hang it up. It all happened after the game against Juventus."