Willian has now revealed that he knew of the Catalan club's offer, but says they were the only side to formalise their interest, despite reports of interest from his former manager, Jose Mourinho.
However, Willian insists he is now happy to remain at Chelsea, after a rift with former manager Antonio Conte.
"I have my head here and I intend to continue in the club unless the club wants to sell me. But my head is here in the club."
New manager Maurizio Sarri managed his first competitive game as Blues boss on Sunday, as Chelsea lost 2-0 to Manchester City in the Community Shield.
Willian, however, believes that Sarri's methods will eventually pay off.
"[Sarri] is a manager who likes to play football, a manager who has a game philosophy similar to Manchester City," he added.
"Manchester City have been playing under Guardiola for a few years now and the players are already adapted [to his style] and already know what to do in the pitch.
"We have just started working with him [Sarri] but in the first days we have seen that he is a manager who likes to shape the game from the back, he likes to play football. It will be very important for us."