(By Paul Virgo)
(ANSA) - Rome, October 21 - When Fiorentina announced in January that they had agreed to pay 10 million euros to sign Giuseppe Rossi from Spanish side Villarreal it looked quite a gamble.
The 26-year-old had been out of action since October 2011 due to knee-ligament injuries and was set to be sidelined for another five months before making a final recovery.
And at the time the Florence club had no guarantee that the Italy forward would be the same fast, unpredictable menace to defences he was before he ruptured the anterior cruciate ligament of his right knee playing for Villarreal against Real Madrid.
Indeed, in the run-up to the start of the 2013-14 Serie A season, much of the attention was taken up by Fiorentina's big close-season signing, Germany forward Mario Gomez.
But while Gomez's impact has been limited to two league appearances due to a knee problem, Rossi is Serie A's top scorer with eight goals in as many games.
What's more, the last three of those goals helped Fiorentina to one of their all-time most memorable victories and one of the worst defeats of their fierce rivals Juventus.
The Turin side looked to be cruising when they were 2-0 up with two thirds of the game gone on Sunday.
But a quickfire hat-trick by Rossi and a goal by Spanish midfielder Joaquin sealed a 4-2 win for the hosts.
Champions Juve had never previously conceded four goals in Serie A after being two ahead.
It was all the more remarkable because coach Vincenzo Montella admitted he was close to substituting Rossi after a poor first-half display following a knock early in the game.
"But then I thought it's always better to give another chance to class players," said Montella.
On Monday Rossi described the Juve win as an "epic" game, adding he had already put the match ball in his trophy cabinet.
Fiorentina Director of Sport Daniele Pradè said there is a lot more to come from Rossi, who was born to Italian immigrants in New Jersey and spent much of his childhood in the United States before joining Parma's academy at the age of 12.
"Giuseppe is still not in the best shape, he can still improve a lot," Pradè said on Italian radio
"But we are very proud of him, he is not even at 70 per cent and he is already decisive. He's still a bit behind physically".
Italy fans are already relishing the prospect of seeing Rossi in attack with AC Milan forward Mario Balotelli at next year's World Cup.
Rossi made his return for the Azzurri after a two-year absence in last week's 2-2 draw with Armenia.
Italy coach Cesare Prandelli said he recalled him despite some fitness concerns because "I want him to understand that he's part of this group".
Rossi's heroics helped AS Roma open up a five-point lead at the top of the table after they maintained their perfect record with a 2-0 win over title rivals Napoli.
Juve and Napoli share second place with 19 points each.
Promoted Hellas Verona are fourth with 16 points after they continued their good form with a 3-2 win over Parma. Inter have 15 points and share fifth place with Fiorentina after being held 3-3 at Torino.
Atalanta climbed to seventh with a 2-1 home win over Lazio and AC Milan are eighth, having scraped a 1-0 victory over Udinese.