Wayne Rooney has also put out a statement of his own following his dismissal.
He said: "I would like to thank Tom Wagner, Tom Brady and Garry Cook for the opportunity to manage Birmingham City FC and the support they all gave me during my short period with the club.
"Football is a results business – and I recognise they have not been at the level I wanted them to be. However, time is the most precious commodity a manager requires and I do not believe 13 weeks was sufficient to oversee the changes that were needed.
"Personally, it will take me some time to get over this setback. I have been involved in professional football, as either a player or manager, since I was 16. Now, I plan to take some time with my family as I prepare for the next opportunity in my journey as a manager.
"Finally, I wish Birmingham City FC and its owners my best wishes in the pursuit of their ambitions."
Birmingham City has today parted company with Manager, Wayne Rooney, and First Team Coach, Carl Robinson.
Despite their best efforts, results have not met the expectations that were made clear at the outset.
Therefore, the Board feels that a change in management is in the best interests of the Football Club.
The Club’s Board and management are fully aligned and will continue to drive transformation and take bold steps to rebuild Birmingham City into the organisation its fans and community deserve.
The Board would like to place on record their sincere thanks to Wayne and Carl for all of their efforts.
It was a match that just never worked for the former England captain.
Rooney was brought in after the controversial sacking of Eustace in October.
Eustace had the best win rate of any Birmingham boss since Gary Rowett, who was in charge at St Andrew's from October 2014 to December 2016.
And so when the new owners gave Eustace the boot, it did not go down well with the fans who were beginning to dream of a play-off finish after the strong start to the season.
