Juventus manager Antonio Conte is anticipating his side's recent dominance of Serie A to be challenged next season.
Conte has guided Juventus to consecutive Italian titles since taking over in 2011.
The Turin club start their 2013-14 campaign at Sampdoria on August 25.
Conte's men finished nine points clear of second-place Napoli last season, but the 44-year-old is expecting a tougher fight next term.
"The values of clubs are changing, our rivals are getting stronger," he told Gazzetta dello Sport. "It will be a very open championship.
"Juve, Milan and Inter are traditionally title contenders. Napoli have spent €75m-€80m and have reinforced with Rafael Benitez, a great coach who has won it all.
"Fiorentina have legitimate hopes. Not only do they have Mario Gomez, but also Giuseppe Rossi, who some are maybe underestimating.
"Lazio have amplified their squad and are tough, tactically strong."
Juventus have strengthened their forward line by bringing in strikers Carlos Tevez and Fernando Llorente in the close-season.
Conte is quick to praise the respective qualities of the duo and has not ruled out more signings before the end of the transfer window.
"Tevez is extraordinary. He's a great professional, a splendid person who puts himself at your disposal. He works in an exceptional way," he added.
"Llorente is a model athlete. He has the right mentality, it is a pleasure to watch him train.
"More signings? We'll see. I've spoken with the club, but I won't tell you what I have said. I know that sales are needed first in order to buy."