Club chief executive Giuseppe Marotta appeared before the media on Wednesday to address a statement released by Inter one day earlier, revealing they had decided to pull the plug on Guarin's exit from San Siro.
Marotta said that Inter president Erick Thohir had agreed the deal via text message with Juve counterpart Andrea Agnelli, before going back on his word.
Inter fans had reacted furiously to reports of the deal, and put Thohir's committment to the club into question - also demanding that the Indonesian businessman make his presence felt more around Inter.
And he could now be under even more pressure, with Marotta blasting Inter's actions as lacking respect to the players involved.
He said: "This press conference was called after the statement released by Inter, which we defined disconcerting. We wanted to set the record straight.
"The Vucinic-Guarin deal was verbally agreed by both parties. Agnelli received a text from Thohir at 10:48 confirming the deal.
"The main reason we called this press conference was the lack of respect shown towards two serious, professional footballers.
"My being here is a necessary act to protect Juventus and the professionals who have been treated unfairly."
Marotta went on to explain that Vucinic is now highly unlikely to move to San Siro, as Inter are unwilling to pay a transfer fee for his services.
"As things stand there's no real possibility that Vucinic could join Inter," he added.
"Inter asked us for permission to speak to Vucinic back in mid-December, that's when negotiations started.
"Once it became clear there was to be no money exchanged, we considered the option of a player swap. Vucinic is a great player.
"If there are to be any future negotiations, Thohir will have to offer an explanation to Agnelli - beyond yesterday's statement."
