The bitter rivalry between the two clubs on the Italian Adriatic coast has intensified since Grosso, who lives near Pescara, took over as coach of their southern rivals last year.
The intimidation intensified in the run-up to Saturday's 2-2 draw between the two clubs at Pescara's Stadio Adriatico.
The outside walls of Grosso's family home in Spoltore, near Pescara, were covered with graffiti, while a rooster, which is the symbol of Bari, was found hanging lifeless at the gate.
Paper bombs were also exploded outside the team hotel the night before the match, in a bid to prevent Bari players sleeping.
Giovanni Loseto, a member of Grosso's coaching staff, was reported to have been threatened with baseball bats by a group of Pescara ultras.
"Unfortunately, the name of Pescara has been sullied by these few individuals," Grosso, a former Inter Milan and Juventus defender who won the World Cup with Italy in 2006, said after the match.
"I don't want to talk about it because I have always lived there, I will always live here and the errors of a few won't change my view that Pescara is a very civilised city."