Juventus are bidding to win a fifth consecutive Serie A title for the second time in their history in 2015-16.
Gianluigi Buffon is expecting a tough season for Juventus, with the captain tipping trio Roma, Milan and Napoli to be the defending champions' main title rivals.
Juventus are the team to beat in 2015-16 as they attempt to win a fifth successive Serie A crown after cantering to the title by 17 points last term.
The UEFA Champions League finalists have added more quality to their already impressive squad, with Paulo Dybala, Mario Mandzukic, Sami Khedira and Simone Zaza now based in Turin.
But 37-year-old goalkeeper Buffon believes 2014-15 runners-up Roma will go close again this time around after bringing in the likes of Edin Dzeko, Mohamed Salah and Wojciech Szczesny.
The veteran Italy international also refused to rule out Milan and Napoli, who both head into the season with new coaches at the helm.
"You can't win indefinitely, even when you are the strongest side. There are teams who have reinforced in Serie A and even begun a whole new era with great enthusiasm," Buffon was quoted as saying by Tuttojuve.com.
"We have the utmost respect for the sides that will challenge us for the title.
"Looking at the transfer market, Roma are certainly the team who reinforced the most this summer.
"Amid the general transformation and the new project under Sinisa Mihajlovic, I also believe Milan will have a very good campaign, especially as they don't have European commitments.
"I think if Napoli fans and players are open to learn from Maurizio Sarri, then they too can be a wonderful surprise."
Juventus open their campaign at home to Udinese on Saturday.comments