The Azzurri international has been strongly linked with Manchester United in the last 48 hours, with the Red Devils reportedly having a bid of around £10m rejected on Friday afternoon.
Baldissoni believes that De Rossi is completely focused on helping the Giallorossi rebuild under new coach Rudi Garcia, reiterating that any bid for his services in the next 24 hours will be swiftly turned down.
He told Sky Sport Italia: "As for De Rossi, we will always reply 'no thank you' to any formal offer that is proposed for him, as would the player.
"Both Roma and Daniele are coming off a year that didn't go well and we want to make up for that together."
De Rossi started for Roma this evening as they continued a 100% start to Serie A with a 3-0 home win over Verona.