FORMER Rangers boss Mark Warburton believes the Ibrox side will have to be patient with caretaker Graeme Murty.
The Englishman also insisted they should not expect to overtake Celtic any time soon.
Warburton, who took over the Govan outfit in 2015 before leaving in controversial circumstances in February last year, said the club need to realise the financial gulf with the champions is widening.
The 55-year-old ex-gaffer, who was sacked by Nottingham Forest earlier this season, said: “You have to recognise Celtic have been in the Champions League now for the last few years, done well to get into the group stage and with that comes financial rewards.
“That increases the gap between Celtic and Rangers. Every year, you are fighting now to close that financial gap.
“The longer Celtic are exposed to Champions League football, the greater the financial divide becomes.
“Rangers need the investment and need to dampen some expectation and recognise they have to build the club back up.
“It is an outstanding club, it is a football institution, it was an absolute privilege to manage up there.
“But you have got to be patient with it, be honest with the fans and give them communication.
“They are aspiring to get back to the top of Scottish football, but it will take time and it will certainly take some investment.”
Warburton added: “Graeme [Murty] has come in he has earnt the respect of the squad, he has got the fans onside and he has done a very good job.
“If you are going to give Graeme that chance, be patient with him.
“Give the man a chance, give him the time, give him the backing verbally and financially that he needs to manage a club of that stature.”
The Ibrox side, who have lost seven league games at home in this campaign, are trailing Celtic in the Premiership by 10 points and Brendan Rodgers’ men also have a game in hand.
The Glasgow rivals meet in the Scottish Cup semi-final at Hampden on April 15 – a defeat for Murty’s side will effectively end their season.
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