The announcement this week of ‘significant’ summer investment on Wearside will have been music to the ears of Sunderland fans.

And even though that promised investment extends only as far as a major facelift for the Stadium of Light, it is no less welcome given that the club’s home has increasingly begun to show its age in recent years.

The installation of safe standing areas, relaying the pitch, adding a new PA system and new floodlights, amounts to the largest overhaul at the stadium since the North Stand extension opened in 2000.

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But improving the stadium infrastructure will be, in many ways, the easy part this summer.

There will be far greater challenges come the close season if Sunderland are to avoid a repeat of the mistakes that have undermined the current campaign.

First and foremost, of course, the club must identify and appoint a new head coach.

That decision will be critical.

Firstly, it will be viewed as an indicator of boardroom ambition - fans will not take kindly to any perceived ‘cheap option’, and instead will expect a head coach with a proven track record of success either at Championship level, or in a major European league.

Secondly, the new man must be able to communicate with fans and be someone they can believe in - the contrast between the warmth and experience of Tony Mowbray and the guarded nature of relative newbie Michael Beale was stark.

And thirdly, it will be critical because the stakes are incredibly high - Sunderland simply dare not get this hire wrong because there has been a sea-change in mood in recent months as the club has continually shot itself in the foot: from the unnecessary sacking of Mowbray to the appointment of Beale, from the Black Cats Bar fiasco to the failure to land a striker in the January transfer window.

So the pressure will be on.

We Are Sunderland: Sunderland sporting director Kristjaan SpeakmanSunderland sporting director Kristjaan Speakman (Image: Sunderland AFC)

But finding the right head coach is only one of the problems that owner Kyril Louis-Dreyfus and sporting director Kristjaan Speakman must solve.

They must also revamp the playing squad, not only to address the deficiencies that have been so painfully exposed this season but also to deal with the likelihood of at least one - and possibly more - high profile departures.

Jack Clarke is viewed as a Premier League player-in-waiting and, after hanging onto him last summer despite interest from top flight clubs, most Sunderland fans accept that he is likely to move on at the end of the season.

Dan Ballard, Dan Neil, Anthony Patterson, and Trai Hume, are also attracting attention.

Clarke aside, even if Sunderland manage to retain their other key assets, they will still have a huge amount of rebuilding work to do.

Of the 13 players who have arrived this season (not including Mason Burstow, who will return to Chelsea at the end of his torrid loan spell), just one - Jobe Bellingham - has gone

on to truly establish himself in the side, with Leo Hjelde starting regularly only due to a catalogue of defensive injuries, while Adil Aouchiche has been in and out of the team.

The three strikers (again, not including Burstow) who signed have been sub-standard, with Ukrainian Nazariy Rusyn the only one who has looked capable of making the step up.

Portuguese youngster Luis Hemir has looked like a fish out of water, while Spanish teen Eliezer Mayenda has been farmed out on loan to Scottish Premiership side Hibernian but can barely even get a game north of the Border.

Collectively, Rusyn, Burstow, Hemir, and Mayenda, have scored three goals in 2,420 minutes; subtract Burstow from that equation and those figures read two goals in 1,525 minutes.

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In short, last season’s recruitment was a failure and it lies at the heart of the club’s travails this term.

Sunderland cannot afford another bad window.

Significant summer investment in the stadium is all well and good, but it must be accompanied by significant investment in the playing squad and a wise choice of head coach.