The news came just days after his superb performance in the rout against Aston Villa.
A close friend told The Sun: “Frank was very emotional during the Villa game especially when the fans were chanting ‘sign him up, sign him up’.
“Their support meant so much to him and that is why he saluted them as he went off, knowing it might be his last appearance at Stamford Bridge.
“He put in a really heroic performance, one that was typical of his time at Chelsea and he felt strong and fit.
“He’s not ready to go and bring an end to the glory days but the club has other ideas. Frank has been a great ambassador for Chelsea and for English football.
“He is everything you would want in a top-class midfield player.
“You cannot measure what Frank has given to Chelsea, it is incalculable and for them to treat him this way leaves a really sour taste.
"He cannot understand why it has come to this.
“Chelsea will never find another player as loyal and devoted as him. He really is Mr Chelsea.”