Indifferent form in the Scottish Premiership and a forgettable outing in the group stage of the Champions League meant that the Dutch tactician was walking on thin ice, with it finally cracking earlier this week.
Rangers find themselves nine points behind rivals Celtic in the league table and as many as ten players are currently set to leave Ibrox next summer.
Adam stressed that the new Gers manager will have to hit the ground running as soon as humanly possible in order to catch up to the Hoops.
While pointing out that the gap needs closing, Adam termed the prospect of Rangers being 15, 16 points behind their rivals at the end of the season unacceptable.
“You know, there’s a number of players out of contract in the summer and you’ll need time”, Adam said on PLZ Soccer.
“Can a new Rangers manager come in and hit the ground running? You have to.
“You cannot go and be 15,16 points behind at the end of the season.
“You have to be closing the gap and have the mindset that we can go and close the gap and change the mentality of this group of players.”
Rangers will take on Hibernian on 15th December in the first fixture when the Scottish Premiership resumes.