The Nigeria international, who currently plies his trade with Tiajian TEDA in the Chinese Super League, spent over ten years at Stamford Bridge.
And speaking on International Youth Day, Mikel sent out a message on Twitter to encourage young footballers by posting a photo of him signing for Chelsea in 2006.
It's International #YouthDay! Remember, work hard and your dreams can come true… trust me! @UN4Youthpic.twitter.com/6ydUOlQpMS
— Mikel John Obi (@mikel_john_obi) August 11, 2018