The summer arrival from Almeria says he is delighted by the introduction he has been given by the club, and feels his fellow attacker should stay put despite interest from England
The future of the 23-year-old Spain international has garnered much speculation in recent weeks, with reports linking him with moves to Arsenal, who have had a bid rejected, and Tottenham.
However, his new Argentine acquaintance has told Marca that the best outcome of the transfer saga would be the ex-Real Madrid youth product remaining in his current surroundings.
"The best thing for everyone is if Juan [Mata] stays, as he can contribute a lot to Valencia this season," said Piatti to the sports daily.
The young attacker has only been at Valencia for a month since his €7.5 million (£6.5m) transfer from relegated Almeria, but has already made a positive impact at the Mestalla, scoring in their pre-season matches against PSV Eindhoven and Sporting Lisbon, and the 22-year-old says he has adapted seamlessly to Unai Emery's team.
"I am happy. Minute by minute I'm consolidating my place [in the team]," said the forward. "What has impressed me is the unity of the group, it is very healthy. There is experience and youth throughout, and we are gelling well."
Piatti also had words of praise for the imminent signing of Sergio Canales, adding: "He [Canales] is a good player, who has many attributes and can help Valencia."