Manchester United have a lot more work to do than many fans anticipated.

Having enjoyed a buoyant pre-season campaign featuring a 4-0 demolition of Liverpool, the Old Trafford faithful were quietly thinking that the Erik ten Hag era could turn things around in the blink of an eye.

However, to say that the Red Devils' opening Premier League game brought them crashing back down to reality would be the mother of all understatements as they floundered to a miserable 2-1 defeat against Brighton & Hove Albion.

Worrying times for Man Utd

But more disheartening than even the result itself was the way in which United allowed it to happen because their performance seemed to have been ripped straight out of the Ole Gunnar Solskjaer playbook.

Now, to an extent, that's to be expected because Ten Hag isn't a miracle worker who can change United's fortunes around overnight as they continue to work through the hangover of Ralf Rangnick's reign too.

Nevertheless, you can can certainly understand United fans wanting to see more cut and thrust from the team in their first outing under Ten Hag rather than another instillment of incoherent build-up play and little to no attacking verve.

And perhaps most damning of all was the way that the Red Devils defended in the first-half as they opened themselves up for Pascal Gross to nab two goals that allowed Brighton to run away with the three points.

From Lisandro Martinez's wobbly Premier League bow to some woeful positioning from Harry Maguire, United's defending was all over the shop regardless of whether or not the midfield was creating big chances.

Rabiot Terms Agreed? Zaha, Aubameyang & Zaniolo Updates (Football Terrace)

Twitter thread of Man Utd's defensive woes

In fact, such was the alarming extent of United's defensive frailties that it has become the topic of a damning Twitter thread unpacking exactly what went wrong for each of Brighton's goals at the 'Theatre of Dreams'.

Compiled by Twitter user @UtdArena, the superb breakdown of the Red Devils' shortcomings made for such an illuminating and alarming read that it quickly picked up hundreds of retweets and thousands of 'likes'.

Dodgy distribution from David de Gea, ham-fisted pressing by Fred and yet more sloppy errors courtesy of Maguire are all documented in the exposing thread that United fans, as well as neutrals, should check out down below:

Now if that doesn't outline the task that lays ahead of Ten Hag then we don't know what does.

So much for Ten Hag to work on

The desperation is two-fold because the thread not only unravels all the painful individual errors that led to the goals, but more importantly, the team traits which paved the way for Brighton to run away with a 2-0 lead.

And that's what Ten Hag needs to focus on as he continues to impress his footballing philosophy upon United, ensuring that all his players are singing from the same hymn sheet to defend as a team unit.

Deviating from the game plan of playing out from the back, losing the pre-agreed team structure and failing to track as a unit are just some of the undesirable habits which are outlined and simply need to stop.

Soccer Football - Premier League - Manchester United v Brighton & Hove Albion - Old Trafford, Manchester, Britain - August 7, 2022 Manchester United manager Erik ten Hag reacts after his team concede the second goal REUTERS/Toby Melville EDITORIAL USE ONLY. No use with unauthorized audio, video, data, fixture lists, club/league logos or 'live' services. Online in-match use limited to 75 images, no video emulation. No use in betting, games or single club /league/player publications. Please contact your account representative for further details.

They say old habits die hard, but that's what it's gonna take for the Ten Hag era to succeed.