DAVE King should have no fears handing Mark Warburton funds to strengthen his squad during the January transfer window - due to the success of the Rangers manager's summer signing spree.

Warburton’s men have seen their once-commanding lead at the top of the Ladbrokes Championship table reduced to three points during a disappointing run which has seen them win just three of their last five league outings.

Archie Knox, who was Walter Smith’s assistant manager at Ibrox for eight years during the Nine-In-A-Row era in the 1990s, believes it is “vital” the Englishman is allowed to bring in more quality players next month.

Rangers came up just short of securing a place alongside the likes of Aberdeen, Celtic and Hearts in the top division when they lost 6-1 to Motherwell over two legs in the Premiership play-off final last season.

The financial implications of that failure were considerable; their annual accounts revealed that additional funding of £2.5 million was needed to enable them to reach the end of the 2015/16 campaign when they were released last month.

Knox feels his old club, who have been linked with Accrington Stanley kids Matt Crooks and Josh Windass as well as Dundee striker Greg Stewart and St. Johnstone forward Michael O’Halloran, must speculate to accumulate in order to avoid that costly fate again.

However, he reckons Rangers should have no hesitation bankrolling the mid-season recruitment drive given how well the players Warburton brought in immediately after being appointed in the summer have fared.

“Mark Warburton has done well with the players he has recruited so far since joining Rangers,” said Knox. “Andy Halliday, Jason Holt, James Tavernier, Martyn Waghorn, the loan signings and others have all done well.

“But he needs more of that. They need to boost their squad just to strengthen their challenge. There will be no guarantees, but it can increase their chances of going up.

“It is more difficult for them than before. They don’t have the finance they have down in England. They don’t have the ability to pay the same wages. But the club can still attract players. He will have the contacts out there and has shown he can be relied on to spend well.”

Knox, who also had spells with Manchester United, Everton and Scotland during a coaching career that spanned four decades, has urged Warburton to target Premiership-standard players during the January transfer window.

“It is vital that Rangers strengthen if they can,” he said. “It’s difficult to get players at this time of year. But I’m sure there will be one or two players you there who will be able to help them win the Championship and also be able to play for the team in the Premiership next season as well.

“If they can do that they must. If they can get one or two of them it will give them a big boost. They need to get guys who are going to be there next season. That is the level of player they should be looking at.”

Meanwhile, Knox has predicted every club in the Premiership will be urging Rangers and Hibs to clinch promotion this season so the money they can bank from broadcasting deals, gate receipts and sponsorship is substantially increased.

Knox said: “The whole of the Premier League will be keeping their fingers crossed Rangers win the title and Hibs win promotion. They will get bigger games, larger crowds and more money if that happens.

“No disrespect to the teams that are in the top flight because Ross County have done really well, Inverness Caledonian Thistle have done very well and Partick Thistle have come up and done alright too.

“But they have missed Rangers and Hibs. Even Dunfermline not being involved has damaged it. I am sure they would get far larger crowds if they were still there. There’s a threat of them losing Dundee United for goodness sake!"