Somehow, words such as embarrassment, humiliation or incompetence don't quite go far enough.

After a particularly eventful decade, I thought I had seen everything as a City fan. How wrong I was.

Saturday made me reassess the fifth-round defeat to Bradford in 1976, which had previously been the worst Cup game I'd ever seen.

That was the year when First Division City lost at home to a side in the lower reaches of Division Four, with sides from Division Two and Three then standing between them and a Wembley final date.

Bradford scored twice from three attempts at goal – or so it seemed – but at least City did everything but score.

Well yesterday's draw opened up a clear-cut way into this year's quarter-finals for City's conquerors, but on Saturday the Canaries themselves never really looked like scoring, other than brief patches either side of half-time.

Luton weren't exactly having to hang on for dear life in the closing stages, either.

With Grant Holt, Wes Hoolahan, Anthony Pilkington and Simeon Jackson completely isolated from the rest of the home line-up it was like there were two separate teams playing Luton with no understanding whatsoever.

Now you can point to the ball not crossing the line in the first half, or the stoppage-time penalty that wasn't, but we didn't deserve anything from this tie. Not even a replay.

Frankly ITV's highlights did an injustice to Luton as they implied that the game was far closer a contest than it actually was.

And to those people still insisting, 'it's only the FA Cup' – well, if you had to field that side against West Brom or Manchester City needing something at the end of the season, how confident would you be about them managing it?

No, we now have six days which will make or break City's season then.

If we're here in a week's time with no new signings and/or having made it eight league games without a win then I wouldn't say we're definitely going down, but we're certainly going to make it very difficult for ourselves to survive.

David McNally and Chris Hughton now have to decide if they can afford not to sign a striker rather than whether they can.

If you can't score at home to a non-league club – or take 27 minutes to create your first meaningful chance – then you're in trouble.

I suppose we should be used to the Canaries being completely ineffective in the FA Cup – that's now a home record of two wins, one draw and five defeats in the last decade – but this was a new low.

Confidence was lacking before Saturday, but what little still remained evaporated as soon as Luton took the lead.

It's a big job to lift players for the remaining 15 games without at least one new face to freshen up things.

City went into the Luton game having won only two of their last nine fixtures – and it showed.

It'll be different players and a different occasion, but we can't afford a repeat of Saturday's attitude.

Paul McVeigh on Canary Call took a typical ex-player's viewpoint in dismissing any suggestion of a lack of passion.

But there were precious few signs of drive, urgency and application.

Until Grant Holt came on and tried to barge his way through the opposition single-handed, we simply never showed any real purpose.

In contrast, Luton came here knowing exactly what they had to do, right from the early moment when striker Jon Shaw made a 'just to let you know I'm here' challenge on Leon Barnett.

I can't blame Chris Hughton for making changes, but when this side failed to set an early agenda it simply let Luton grow in confidence and ultimately take ontrol

There were a number of reasons why Luton won – but for me the main one was that they started with Shaw and Gray up front, and once they'd run themselves into the ground they were able to bring on two fresh forwards in the form of Stuart Fleetwood and Scott Rendell.

This was the game that should finally have convinced everyone that our striking capabilities simply aren't good enough to guarantee to keep us up.

Harry Kane simply isn't up to it yet, and we can't afford another last-gasp piece of transfer business like that on Thursday.

Or the desperate – and ultimately unsuccessful – attempts to land David Cotterill in 2006.

This is the time when you need your high-powered and high-paid staff to pull out all the stops and earn their packages by having a Plan A, Plan B and Plan C in place.

It's not a good time to be trying to sell very expensive season tickets, especially if there's a risk that they'll entitle you to see Tranmere rather than Liverpool next year.

The Canaries still ought to have enough about themselves to avoid the drop, but it's going to be a big week to lift themselves.

It's not a good week to be playing Tottenham after their result yesterday, while who knows who we'll be facing at Shepherds Bush on Saturday.

Despite Harry Redknapp's staged anger in front of the cameras, QPR must have considered the possibility of losing to MK Dons, as did Aston Villa at Millwall.

But the Canaries against Luton? No chance. And that's the thing now, the complete collapse of confidence seen following Scott Rendell's goal is now the biggest hurdle facing Hughton.

If we lose to QPR they will see us as catchable. If we can maintain our current advantage, 11 points is a lot to lose in just 13 remaining fixtures.

But we cannot go to Loftus Road with the same approach of lumping the ball forward as our only real option and some non-existant passing.

Those are the sort of non-league tactics that City have been able to brush aside in the past, but on Saturday they were completely undone by a club who couldn't win at AFC Telford in their previous away outing.

We can't brush Saturday away as a one-off, with a much weakened line-up, because that team should still have been good enough to get the better of a team four levels below them.

The warning signs were there against Newcastle and Liverpool. They cannot be ignored again.

• WARNING: FANS NEED TO GROW VERY THICK SKIN

Was that a more embarrassing result than Colchester? Or Fulham in 2005? Or Charlton in 2009? Without a doubt, yes.

Forget the actual match, because, whatever the merits of individual displays, that won't be remembered at all.

What will be is the final score. And it will continue to be until someone else in the Premier League is stupid or puts in a half-hearted-enough performance to get knocked out by non-league opposition.

Now Fulham might score six against someone again, and maybe Colchester might hit seven soon, but league embarrassments get forgotten very quickly. There's always another display of incompetence around the corner.

But the FA Cup is different – big clubs being embarrassed are always dragged up season after season.

Now as much as you can point to Luton not really being of non-league calibre, or the rights or wrongs of how the football authorities effectively expelled them after bending over backwards to help MK Dons, there's no getting away from their current status.

When City lost at home to Bedford in the 1956 first round there would have been very little to choose between the clubs. That season Norwich finished bottom of the Third Division South, while the visitors were second in the Southern League – effectively a gap of two league places.

In every aspect of the modern game – turnover, crowds, staff numbers, transfer fees, stadium facilities – the Canaries are light years ahead of Saturday's opponents.

Every time the latter stages of the FA Cup roll around we see Ricky George scoring for Hereford against Newcastle and Sutton's Matthew Hanlon striking against Coventry. Without fail.

We are now going to have to get used to seeing Scott Rendell's effort join that select band.

People who ask 'aren't we all over-reacting?' perhaps don't fully appreciate the ignominy of Saturday's defeat.

Never mind Coventry's failing against Coventry, it's 27 years since a top-flight club last lost at home to non-league opposition – a season, incidentally, when Birmingham followed up defeat to Altrincham by also getting relegated – and 64 since one was beaten at this stage of the competition.

In other words, this result could still be referenced in 2040 or even 2079. You have been warned.

• LUTON SUPPORTERS DESERVE RECOGNITION FOR EFFORTS

The one thing that shows that Luton aren't your average non-league club was the level of their support on Saturday.

I'm sure they could have shifted far more tickets had they been available.

You look back to 2003's fourth round and the visit of Dagenham & Redbridge, the most comparable occasion to the weekend, and although they had a following of 2,116 their support didn't have quite the same intensity as Luton's.

It was a bit of a role reversal between the third and fourtth rounds – but that's the way the FA Cup works with a bigger away ticket allocation. The City support created far more atmosphere at Peterborough, but a more subdued home following were outdone by the away end on Saturday.

It could be quite some time before we see an away following on that scale at Carrow Road, given our complete ineptness in cups.

There were 3,360 Tottenham fans here in the Capital One Cup earlier this season, but apart from Chelsea in 2002 and West Ham four years later in the FA Cup that's really been it for large followings for many, many years.