Ulster coach Mark McCall has resigned from his post with immediate effect following the Irish club's recent run of poor form.
McCall, who was appointed to the head coaching role in 2004, has been under pressure following Ulster's dire start to the season culminating in a 32-14 defeat to Gloucester in the opening round of the Heineken Cup at Ravenhill on Friday.
The 39-year-old officially tendered his resignation on Monday evening.
Ulster Rugby chief executive Michael Reid held a press conference on Tuesday which formally announced the resignation of McCall and read the following statement: "Mark McCall tendered his resignation to myself and chairman Cecil Watson yesterday (Monday) evening.
"This offer was considered and accepted with regret by the professional team management committee later last night.I have met this morning with Steve Williams who has taken charge of team affairs with immediate effect.
"The poor results this season have been very difficult for us all and ultimately have brought us to where we are today, however, I believe strongly that the following is recorded.
"Mark McCall has been an outstanding committed coach for Ulster, meticulous in his preparation he endeavoured to create an environment of empowerment for the players.
"During his three years in the job, nine players received international recognition, a greater number of new caps than at any stage since the game turned professional, and an achievement which was down to the player identification and hard work of Mark and Allen Clarke.
"Over the weekend, one Sunday one paper quite rightly stated, 'If Mark McCall came into work any earlier he would meet himself leaving' - his drive, passion and enthusiasm for Ulster Rugby is immense."
In a statement, McCall said that he had been privileged to have coached the province that he had played for: "Over the last three and a half years it has been an absolute privilege for me to have been coach of the Ulster Rugby team.
"Winning the Celtic League two seasons ago was a huge highlight and it has been very rewarding to watch the Ulster representation in the Irish squad rise year on year.
"During my time I have received fantastic support from the Ulster Branch and I am grateful to have worked with a very professional management team who have become friends as well as colleagues.
"I believe the time is right for someone else to take the team forward and I would like to wish all concerned every success in the future."