Caretaker manager Kenny McDowall has left Rangers, the club have announced.
McDowall has been in charge of first-team matters since Ally McCoist resigned as manager and was placed on gardening leave in December.
McDowall leaves Rangers in third place in the Scottish Championship, five points behind second-place Hibernian and 22 behind league leaders Hearts.
Former Motherwell boss Stuart McCall is set to be announced as Rangers manager until the end of the season.
On 19 January McDowall followed McCoist in tendering his resignation, signalling his intention to quit the club at the end of his 12-month notice period. However, he will not see that out.
Walter Smith brought McDowall to Ibrox as part of his coaching staff from rivals Celtic - where he served as youth and reserve team coach - in January 2007.
When Smith stepped down from the manager's position in 2011 to be replaced by McCoist, McDowall was promoted from first-team coach to assistant manager.
"It was an honour and privilege to work for Rangers Football Club and I will leave with so many positive memories," McDowall said in a statement on the club's website.
"I have worked with so many talented people since I joined and I will forever be in Walter Smith's debt for bringing me to Rangers.
"Working with Walter, Ally McCoist, Ian Durrant, Jim Stewart and all the backroom staff plus the staff at Ibrox and Murray Park was a pleasure and I wish the club well for the future.
"I was delighted to play a part in the club's history and I wish the supporters and new management team all the very best."
Interim chairman Paul Murray said: "Everyone at Rangers Football Club thanks Kenny for his contribution and we will never forget the part he played in our success since he joined under Walter Smith in 2007.
"He is a man of integrity and honour and gave everything during his time at the club.
"Kenny worked under extremely challenging circumstances in recent months but he always gave everything he could to try to secure results for the football club."
McCall is expected to be announced as the new Rangers manager later on Thursday.