The former Scottish secretary says he felt "publicly humiliated" when he was sacked by Sir Keir Starmer.
Ian Murray said he was expecting to hear "something nice" from the prime minister, but instead he was told by Starmer that he wanted to "refresh the team".
Murray - who is Scotland's longest serving MP - was replaced by Douglas Alexander following the resignation of Angela Rayner earlier this month.
Speaking to Times Radio at the Labour conference in Liverpool, Murray admitted he felt “frustrated” after learning of his sacking as he believed he was doing a good job.
“We’d put the Scotland Office back on the map, got a really good spending review, most of it being announced by my successor in the last week to ten days,” Murray said.
“I felt a little bit publicly humiliated, if I’m being honest, which I thought was unfortunate and not necessary. I was preparing to go back to the backbenches, then 24 hours later was offered a different job as a minister of state in two big departments, which I’m very happy about.
“I don’t know what the process was but things turned around in 24 hours.”
The Edinburgh South MP now serves as minister of state in the Department for Culture, Media and Sport and the Department for Science, Innovation and Technology.
Read the full story on The Times website.