The deal will tie the superstar to the club until 2018, and while it was never a realistic possibility that Barca would part ways with the four-time reigning Ballon d'Or winner, Rosell said the Blaugrana had not had any potential suitors or offers for the Argentine star.
"The club has never received any offers for Messi," Rosell told reporters. "I'm sure if he has had them, he dismissed them."
The 25-year-old Messi will become the third star player in a week to commit his future to the Blaugrana following the news of Carles Puyol and Xavi Hernandez agreeing to contract extensions, and Rosell is hopeful goalkeeper Victor Valdes will follow suit.
The 31-year-old stopper has publicly stated he will not be extending his contract with the Catalan giants, but the Barca chief insists a change of heart should not be ruled out.
"He said he wanted to quit Barca. Do not rule anything out. I still hope he will change his mind," Rosell said.