Middlesbrough Football Club confirmed this evening that Tony Mowbray has left the club with immediate effect.
Assistant manager Mark Venus will take charge of the team until further notice.
In a brief statement, Middlesbrough FC paid tribute to its former captain, who had returned as manager in 2010:
The club would like to place on record their sincere thanks to Tony Mowbray for all of his substantial efforts, dedication and integrity. He leaves with the very best wishes of all at the club.
More top news
Police have released CCTV footage in an attempt to trace two men they want to speak to after a serious fire at Fisher Court in Ripon.
Hundreds of images have been unearthed of soldiers who posed for photos before they went into battle at the Somme.
Newcastle United have bolstered their medical department with two new appointments in the hope of improving the club's injury problems