ALLY McCOIST believes only significant investment will solve the many problems facing Rangers regardless who the club appoint as manager and director of football.

In his most open interview since leaving Ibrox two years ago, the former manager and all-time top goalscorer of what he still describes as his club, made it clear Dave King and his board must find more money from somewhere or forget about closing the gap to Celtic.

McCoist also passionately defended himself when asked about not voting in a vital AGM for the current board as they attempted to rid the club from the influence of Mike Ashley and the Easdale brothers.

Read more: The big interview: Ally McCoist on Celtic dominance and why the Rangers supporters' patience has all-but disappeared

Rangers remained adamant last night that the non-arrival of Ross Wilson, who had been targeted to fill the director of football role at Ibrox, will not distract them from pushing ahead with the deal to bring Pedro Caixinha to the club as manager.

Wilson’s decision to stick with Southampton, is not seen within Rangers circles as ‘a catastrophe’ but more a ‘long-term project,’ while ‘all energies’ are being directed towards recruiting Caixinha soon

However, when McCoist was asked his opinion on Caixinha, it was obvious what he felt was the most important issue.

“Anyone as manager is a risk at the moment,” he said. “I actually don’t think the manager is the biggest thing needing sorted out. It goes a lot deeper than that.

“The club needs investment. I don’t think it’s rocket science. I know a lot of people talk about directors of football and all that. I just think that is absolute nonsense. It has nothing to do with directors of football. It’s about players on the park and the club needs investment to get that.

“In 2007, Walter (Smith) went back to Rangers after Paul Le Guen. He spent around £2 million on Carlos Cuellar, the same on Steven Naismith, Steven Whittaker and Kevin Thomson. Davie Weir we got for free. Daniel Cousin came in. Steven Davis arrived initially on loan and then we spent £2 million to sign him.

Read more: The big interview: Ally McCoist on Celtic dominance and why the Rangers supporters' patience has all-but disappeared

“Within a year the club was in a UEFA Cup final. Celtic thoroughly deserved their title but, with the greatest of respect, that run probably cost us the title.

"Until there is investment, I think we will be having this conversation next year and the year after”

The problem is King’s reluctance to spend more than he pledged and no rich outside investors appear to be on the horizon.

However, McCoist said: “It’s just a fact the club needs financial investment. In my last year before it was announced I was leaving, I think we had 25 games. We won 19 of them. We beat three Premiership teams and never lost a goal.

“Have we moved on? Were we good enough then to challenge Celtic? No chance, absolutely no chance. I don’t think the goalposts have moved that much. Until there is serious investment I think it will be the same.”

It was put to McCoist that Rangers would be, to put it mildly, unwise were they to return to the bad old days of spending massive sums on transfers and wages.

He said: “You can do that within your means. Of course I don’t want to put the club in any jeopardy like it was in before. I think there were special circumstances for the club going into administration and liquidation.

Read more: The big interview: Ally McCoist on Celtic dominance and why the Rangers supporters' patience has all-but disappeared

“There was the crash. I know for a fact the debt at Rangers Football Club at that particular time was 100 per cent manageable. There were alternate motives or reasons for the club going into administration and liquidation. As you know the vast majority of clubs run at a debt. Rangers’ was manageable then.”

And to the accusation McCoist did not do his duty by Rangers when he didn’t vote for King to win 75 per cent of shareholder approval, known as Resolution 11, he said: “The criticism was completely unjustified and unfair. The fact of the matter is 25 per cent of the shareholders didn’t vote of which I was one of.

“And of the 75 per cent who voted a total of 26 per cent voted against Resolution 11. Not only did I not vote against them, I was one of the 25 per cent who didn’t vote because I was away doing Champions League work.

“I turned up initially to vote for the board and oust the previous board strongly against my lawyer’s advice.”