The Riverside club said that Southgate’s 3½-year rein had been brought to an abrupt close shortly after his team had beaten Derby County 2-0 to move within touching distance of league leaders West Bromwich Albion.
In a 40-word statement on the club website, Boro officials confirmed that their former captain had been relieved of his duties, as well as his former Crystal Palace manager Alan Smith, who had been brought to the club in an advisory capacity.
The brief statement said: “Middlesbrough FC have tonight announced that manager Gareth Southgate has been relieved of his position with immediate effect. Football consultant Alan Smith will also be leaving the club as part of the change. Further details will follow here very soon.”
Coaches Colin Cooper, a Boro stalwart, and Steve Agnew are expected to be placed in temporary charge of the club as chairman Steve Gibson seeks Southgate’s replacement, with Alan Curbishley and Paul Jewell expected to be in the running.
Gibson is renowned for his loyalty, but his patience has been tested by the growing unrest among supporters, with more and more fans turning their back on the club.
Tuesday night’s attendance of just under 18,000 was the lowest League crowd the Riverside Stadium has witnessed, with fans becoming exasperated by the team’s inability to raise their game on home territory.
Southgate, a former England defender, moved from the dressing room to the manager’s office when he took over the Boro reins from Steve McClaren, who was appointed national team manager after the last World Cup finals.
Unlike McClaren, Southgate has had to cope with a severely restricted budget as Gibson has tightened the purse strings, and was unable to stop the club’s gradual slide down the pecking order.
Southgate, whose five-year contract was due to expire at the end of next season, insisted that he would not quit, but Gibson has moved decisively in an effort to restore his hometown club to the Premier League.