Rangers' failed pursuit of Derek McInnes has left the club "embarrassed" and the Ibrox board looking "clueless", says former midfielder Derek Ferguson.
The Aberdeen manager opted to stay at Pittodrie on Thursday after "weighing up" an approach from Rangers.
"I'm absolutely stunned. I thought it was a gimme once Rangers were pursuing him," Ferguson told BBC Sportsound.
"It's a bit embarrassing. For a club of Rangers' stature to be six weeks without a manager is not good enough."
Rangers sacked former manager Pedro Caixinha six weeks ago on 26 October, with caretaker boss Graeme Murty leading them to four wins and two defeats in the interim.
He is likely to remain in charge for Saturday's home Premiership game against Ross County.
"Rangers have put their eggs in one basket," Ferguson noted. "The directors don't seem to have a Plan B. They just look clueless at the moment.
"Embarrassing? To me, and all those Rangers supporters. There has been no clarity.
"At the AGM the chairman Dave King said they were looking at certain people in employment. Well it has not worked out and it is not good enough. Is it going to take another six weeks?"
Ferguson, who played more than 100 games for Rangers, believes their failure to appoint a permanent successor has cost them further ground on Glasgow rivals Celtic. They are seven points behind in the Premiership, having played a game more.
"At times players look for excuses and they have got the biggest excuse of all, that they have not got a manager there to answer to," he added.
"Graeme Murty has come in and done fantastically well, but I look at the other side of it. The two games Rangers lost, to Hamilton and Dundee - if a Derek McInnes was in as manager, I don't think they would have lost those games.
"If they had won those games, they would be a bit closer to Celtic."
Ferguson believes that McInnes, who spent five years at Ibrox as a player, was not convinced Rangers would give him the level of input into all aspects of the club he has at Aberdeen.
"I thought emotion would have played a huge part in it, looking at Derek being a Rangers supporter and having played for the club as well," he added.
"There are some things that he has had a look at. The couple of days people are saying that he has spent time with his family, I think he has looked at all aspects.
"Would he have control of just the first team? Mark Allen, the director of football - would that relationship work?
"In my opinion Derek would have liked to have had a bit of input, certainly in the academy side.
"Looking at it from the outside, I think he has not got those assurances, and that is why there are huge question marks."