THERE have been a fair few seismic summer signing sprees at Rangers down the years. Some, like those carried out by Graeme Souness, Dick Advocaat or Mark Warburton immediately after they had been appointed as manager at Ibrox, proved resounding successes. Others, such as those conducted by Paul Le Guen or Warburton last summer, rather less so.

It will be interesting finding out in the coming weeks which category the extensive recruitment drive – he has brought in no fewer than five new faces to date and that number is expected to rise to double figures in the coming days - Pedro Caixinha has been on in recent weeks falls into and how his acquisitions fare in this country.

Will Bruno Alves, Fabio Cardoso and Dalcio have the ability and intelligence which the Portuguese coach felt many members of the squad he inherited lacked when he arrived in Scotland last season and be better placed to implement his game plan? Or will they prove to be ineffectual and expensive foreign imports like Filip Sebo, Libor Sionko and Karl Svensson and flop? Time will tell.

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Yet, one thing can be said with absolute certainty before a ball is kicked in the 2016/17 campaign by Alves, Daniel Candeias, Cardoso, Dalcio and Ryan Jack, Eduardo Herrera, Alfredo Morelos and Carlos Pena, if their work permits are granted, or Graham Dorrans and Jamie Walker, if improved bids are accepted.

Namely, that the best signing Rangers will make this summer will be their new director of football Mark Allen.

Ally McCoist was dismissive of the importance of creating such a position at the club he served for decades as a player, coach and manager when he spoke to the media towards the end of last season. “It is absolute garbage if anyone thinks it will solve all of Rangers’ problems just now,” he said.

They Ladbrokes Premiership club certainly have, despite over 40,000 of their supporters renewing their season tickets, huge off-field issues which still require to be addressed if they are ever to savour the sort of domestic and European success which they once did.

But bringing in Allen, the current Manchester City Academy director, will be a significant part of their rebuilding process all the same and should ultimately ensure a far better run and more financially stable club in the future.

The sudden departure of Warburton, along his head of recruitment Frank McParland, back in February left Rangers without anybody scouting players and identifying possible signing targets. It was, quite frankly, a ridiculous and dangerous position for a club of such a size to be in approaching the close season. Especially with so many personnel who are clearly not up to the task.

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Should Allen - the former Swindon Town professional who spent some time working as managing director of broadcast services at MTV Europe before taking up his current position with City - complete his move to Rangers he will oversee the entire football operation from the youth set-up to the first team.

If the Welshman does well he will help to ensure that fewer mistakes are made in the transfer market and less money is squandered. If there is a change of manager his presence will limit the upheaval and ensure greater continuity

The massive importance of having an effective director of football in the modern game was driven home to me last week after Sunderland made an official approach to Aberdeen for Derek McInnes.

The Stadium of Light club has gone through five full-time managers – Paolo Di Canio, Gus Poyet, Advocaat, Sam Allardyce and Davie Moyes - in as many years and it was no great surprise to anybody in English football when they were finally relegated from the Barclays Premier League last season.

Speaking to Sunderland supporters about the anticipated arrival of McInnes - in the days before the Scot decided to remain at Pittodrie - it became apparent many felt the real blame lay elsewhere.

“Our recruitment has been shocking time and time again,” said Stephen Goldsmith of the Wise Men Say podcast. “We have had a succession of directors of football and sporting directors who have bought players with no sell-on value for millions of pounds who failed to hold down first team places and whose contracts just ran down.”

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Caixinha has brought in players who he knows personally, has seen in action or have been recommended to him through the contacts he has built up in the game. He was urged, for instance, to buy Morelos, the Columbian striker who did well for HJK Helsiniki in Finland, by his first team coach Jonatan Johansson.

It is farcical for Rangers to rely solely on their manager to strengthen and puts them at a distinct disadvantage to Celtic. Allen coming in will rectify a highly unsatisfactory situation.