It is ironic that the devastating manner in which Jose Mourinho has approached transfer business this summer is one of the very reasons Manchester United were so wary of him in the first place.

United have recently been a bit sniffy about the crash-bang-wallop approach to buying players. Mourinho's tendency to assemble squads quickly and expensively was always a little garish for a club that, publicly at least, liked to mix and match top European talent with younger players from their own academy.

In spending well in excess of £150million over the past eight weeks, however, Mourinho has become the first United manager since the retirement of Sir Alex Ferguson to recognise a simple truth - namely that the roster of players at Old Trafford has simply not been good enough.

Manchester United boss Jose Mourinho has been busy in the transfer market

Mourinho has been quick to address United's deficiencies within their squad

Mourinho watches his squad train at their Aon Training Complex on Thursday

Juventus' Paul Pogba is set to be Mourinho's fourth summer signing at £100m

Pogba left Old Trafford on a free transfer in 2012 after a lack of first-team opportunities

Pogba (centre) as a young boy alongside his older brothers Florentin (left) and Mathias

Pogba took his mother Yeo as his guest to FIFA's Ballon d'Or gala in January

Pogba smiles alongside Wayne Rooney, while taking his skills to kitchen (right)

Hair today, gone tomorrow might be the best way to sum up Pogba’s approach to his barnet. He has notable flair in the way he unveils each new do, picking the biggest matches to debut his latest style

SUPER STAT United fans should expect Pogba to get stuck in - the midfielder committed 87 fouls last season, the second most in Serie A. He picked up 10 bookings but wasn't shown one red card. Advertisement

We can argue all we like about the valuation of Paul Pogba, for whom United have agreed to pay Juventus just shy of £100m. Does the fee seem rather high? Yes, of course.

Will the fee matter if the Frenchman helps United back into the Champions League and gives them a decent run at stealing away Leicester City's Premier League title? No, of course not.

As with most buys in football, it is useless trying to assess this one's astuteness until Pogba has spent a period of time on the field. Instead, it's more interesting to look at Mourinho's summer as a whole.

He has brought in Eric Bailly (£32m), Pogba (£100m), Henrikh Mkhitaryan (£35m) and Zlatan Ibrahimovic (free).

Zlatan Ibrahimovic joined the Red Devils on a free transfer from PSG this month

Henrikh Mkhitaryan (left) and Eric Bailly cost United a combined £67m this summer

These aren't fripperies. These are fundamental signings to address fundamental issues.

If importing a completely new spine into your football team in one summer does not highlight the inadequacies of what you have inherited from those who have passed before you, then nothing ever will.

Indeed, the decisiveness with which United's new manager has acted since he replaced Louis van Gaal at the end of last season has been interesting because, among other things, it has been so at odds with what Van Gaal and David Moyes did previously.

Had Moyes not prevaricated so much when United were on the verge of signing Thiago Alcantara from Barcelona three summers ago, then Pogba may not even have been required. Alcantara has since won three Bundesliga titles with Bayern Munich.

Equally, Van Gaal's endless talk about promoting young talent from the ranks is finally exposed as disingenuous baloney now that Mourinho has run his eye over Andreas Pereira, Paddy McNair, Tyler Blackett and Cameron Borthwick-Jackson and decided that they are not good enough - not yet anyway.

Thiago Alcantara has won three Bundesliga titles since joining Bayern Munich

Tyler Blackett (left) was deemed a promising talent under Louis van Gaal

Of all the self-obsessed rubbish spoken by Van Gaal during his lamentable tenure, that which centred on Old Trafford's young players was the most offensive. It was astonishing some chose to buy into it.

Borthwick-Jackson and others featured in last season's first team not as a result of some grand plan but because Van Gaal's lack of foresight left him with no alternative.

It should always be remembered that the one great success of his second season, striker Marcus Rashford, was not even taken on tour at the start of a campaign that ended with him playing for England.

Blackett, McNair, Pereira and striker James Wilson all travelled to the USA in July 2015 with the United first team. Rashford did not.

It was on that tour that United's executive vice-chairman Ed Woodward spoke of how Wayne Rooney would lead Van Gaal's search for goals in 2015-16 with back-up from signings Memphis Depay and Morgan Schneiderlin.

How long ago all that seems and it would appear that Woodward is among those already benefiting from a dose of Mourinho reality only one year later.

Marcus Rashford's rise came as a result of a lack of foresight from Van Gaal

Mourinho's approach to the market can grate a little. It has never been graceful and followers of other clubs regularly chided for spending heavily in pursuit of trophies will no doubt ask when the bar charts measuring United's summer outlay will appear on newspaper websites. It is a fair point.

But the Portuguese has never claimed to be a director of football. Mourinho is not a long-term planner. He is a serial accumulator of trophies and he is in Manchester to reverse a decline in playing standards that actually started at Old Trafford even before Ferguson left in early summer 2013.

Unrecognised by most, a big hole was beginning to open up beneath United's first-team squad during Ferguson's last seasons and only the Scot's tendency to overachieve kept the club from plummeting straight into it.

Once Ferguson's succession was bungled, England's biggest football club succumbed to gravity. It would be unfair to criticise Mourinho for trying to reverse a three-season decline the only way he knows how.

United's glaring problems started under legendary boss Sir Alex Ferguson