MARK WARBURTON last night launched a passionate defence of his record as Rangers manager which came with a warning to the club’s supporters that it will be years before Celtic could be realistically challenged.

He insisted second place was always the goal for this season, not the message put forth by everyone inside Ibrox last summer, and admitted the club is still working out a way to bridge what is the biggest gap ever between the old rivals and conceded Celtic are going to become even more financially powerful.

The Englishman’s standing among a previously loyal fan-base has slipped in recent weeks - even when the team won matches - but the manner of their 4-1 defeat to Hearts made even those who have continued to back him question whether a change was needed.

Read more: Mark Warburton Q&A: The Rangers manager lays bare the worrying state of his club in the wake of another awful performance

Warburton, however. pointed out that Rangers have never been in this position before and therefore it was expecting too much for them to push Celtic in their first season back in the Premiership since the club was placed into liquidation in 2012.

He said: “When was the previous time Rangers had been down to the bottom division? It’s unprecedented. The club is coming back. Let’s be clear. Senior supporters have come up to me and said, ‘the club’s never been like this before’. They’ve always been at the top. They are right.

“The club’s pedigree is outstanding. The history of the club is magnificent. But we’ve never been to the lowest level before and had to fight our way back.

"The club is coming back from a very, very low ebb, a very, very tough time. To come back and get promotion was last year’s target and we achieved it.

“What I’d like you guys to say is, ‘there is a big gap alright, but finishing second and getting in to Europe is not a bad achievement’”

Warburton said it would be “unacceptable” if Rangers did not finish second, a position he appeared to believe would be the club’s best case scenario for some time to come.

He said: “Do we want to be 25 points behind Celtic? No, but our focus right now is Rangers and getting second in the table. That's what we have to do. Get back into Europe and it's another box ticked. Qualify for the Europa League if we can. Another box ticked.

Read more: Mark Warburton Q&A: The Rangers manager lays bare the worrying state of his club in the wake of another awful performance

“We are not going to close that gap quickly. We're not. But if we are more transparent with our fans, telling them what we are thinking and what the club are trying to do.

“We can't buy a £20million striker. I would love to, but the club can't be reckless in our spending. We have to be on solid financial ground. As boring as that may sound it's what the club has to do.”

Rangers supporters deep down will know this. Unless Dave King, the owner changes his tact and makes a heavy investment, or someone outside of Ibrox invests, then it is almost impossible to see when Celtic won’t have it all their own way in Scottish football.

Warburton said: “We have to build. Where should we be? Challenging Celtic and challenging for the league - that's where we need to be. And right now we have a situation where the financial income they have from the Champions League makes it a vicious circle. There’s £30-odd million coming in.

“How do we close that gap? We have to find a way. But is it easy? Absolutely not.

“We are not in the Champions League next year - they are. So the gap could widen again. But we have to find a way. Time and giving young players a chance to develop is one way. But we are just being realistic. I understand history - I get all that - but this is literally an unprecedented situation.”