Alan Smith argues the case for Ljungberg, Henry, Bergkamp and Pires...

Last week someone posted on Twitter a picture claimed by the author of being the Premier League's best ever front four.

There they stood during training in perfect formation - Freddie Ljungberg, Thierry Henry, Dennis Bergkamp and Robert Pires, the magnificent strike force of Arsenal's 2003/04 title-winning campaign.

This got me thinking. Do those famous Invincibles really rank as the greatest so far if we look at champions down the years fielding four attackers? Not all of them have done that, of course. Plenty preferred 4-3-3 or 4-1-3-2, which rules them out of this particular competition.

Yes, I know it's subjective, far from an exact science. I mean, do you judge on individual talent or the group as a whole? Do you factor in great chemistry and understanding that may have made a foursome so much more than the sum of its parts?

5:06 A look at some of the greatest goals ever scored in the Premier League, including Cristiano Ronaldo's iconic free-kick as well as many more memorable strikes from down the years A look at some of the greatest goals ever scored in the Premier League, including Cristiano Ronaldo's iconic free-kick as well as many more memorable strikes from down the years

Whoever you end up choosing, there's a valid argument for heading elsewhere. Still, with time on my hands in these strange days, I thought I would take a look back at the attacks of the 27 victors since 1993. Of those that qualify, which of these teams boasted the finest front four?

Naturally kicking us off are Manchester United's back-to-back title wins in '93 and '94. Yet for all the swashbuckling thrills over two seasons you could not really name a regular four, what with Ryan Giggs, Andrei Kanchelskis and Lee Sharpe sharing wing duties, while Brian McClair partnered Mark Hughes before Eric Cantona's arrival.

Blackburn strike force of Alan Shearer and Chris Sutton hoist the Premier League trophy in 1995

Moving on, Blackburn Rovers deserve a mention in passing, if only for the potency of Alan Shearer whose SAS partnership with Chris Sutton got handily serviced by Jason Wilcox and Stuart Ripley.

When United took over again to register consecutive title wins in '96 and '97, David Beckham's emergence on the right and Giggs' progress on the left cannot quite do enough to put an attack also featuring Cantona, Andy Cole and Ole Gunnar Solskjaer in the top bracket.

That all changes a couple of years later, though, when Dwight Yorke arrives to forge a spectacular partnership with Cole. And if we are judging on trophies, United's sensational treble in '99 makes a convincing case for Beckham, Yorke, Cole and Giggs qualifying as the Premier League's greatest strike force.

That argument gains even more ground considering these four played key parts in three titles in a row, a feat no other club has managed to achieve.

No other club apart from Arsenal has gone through an entire season unbeaten either, which partly explains why Ljungberg, Henry, Bergkamp and Pires could win the top prize.

Freddie Ljungberg, Thierry Henry, Dennis Bergkamp and Robert Pires during an Arsenal training session in 2004

There's more to it than that though. Much more. For a start, Henry is the best player I have ever seen ply his trade in this country. Not just the best striker, but the best player, due to the fact that I saw him do things no one else has done.

He reduced top-class opponents into helpless also-rans. He totally embarrassed seasoned professionals with his outrageous pace, strength, skill and confidence. In short, he elevated the striker's art on to a level not seen before or since.

On top of that, the Frenchman teamed up with a player blessed with astonishing ability, whose creative genes dovetailed perfectly with all that Gallic swagger. Bergkamp's sort do not come around too often. The Dutchman's dedication set new examples at Arsenal and his quality on matchdays lit up English football.

Henry and Bergkamp. I can't think of another strike partnership in the history of the game that has boasted quite so much lavish talent. Alan Smith

To be honest, I cannot think of another strike partnership in the history of the game that has boasted quite so much lavish talent. Some statement, I know, but I think it's true.

And when you add the gliding class of Pires and the piercing threat of Ljungberg, you really do have a fearsome four.

So has anyone since come close to these two front runners - United's all-conquering attack and Arsenal's Invincibles?

To be honest, I was going to talk about Chelsea's first title wins in '05 and '06 when Arjen Robben and Damien Duff brought so much width and flair to Jose Mourinho's side. In my mind, I thought they often flanked both Didier Drogba and Eidur Gudjohnsen, only to find that these four hardly ever started together, Mourinho much preferring a midfield three.

As for United's next dominant period when they once again clinched three titles on the trot, a combination of Cristiano Ronaldo, Wayne Rooney, Carlos Tevez and the indomitable Giggs also takes some beating.

Cristiano Ronaldo, Carlos Tevez, Wayne Rooney and Ryan Giggs formed a fine front four for Manchester United

In more recent times, Manchester City's success must be recognised. Samir Nasri, Sergio Aguero, Edin Dzeko and David Silva were often the choice in City's victorious 2012 campaign.

Even more recently, Pep Guardiola has triumphed with a three-pronged attack, which unfortunately means they cannot be considered. The modern day habit of rotating also muddies the waters. Rarely do managers pick the same attack for any length of time.

That applies to nearly every champion since 2010, with the honourable exception of Leicester City who pulled off a miracle in 2016 with Riyad Mahrez, Shinji Okazaki, Jamie Vardy and Marc Albrighton leading the charge.

But back to the contenders. Back to my verdict. As I replied to that Twitter post mentioned at the start, the Arsenal lads get my vote. And I say that trying hard to avoid any bias towards my old club. The United front four that straddled the Millennium with tremendous success comes extremely close. It's difficult to argue with piles of silverware.

But I'm going for the quartet led by Henry and Bergkamp, who tip the balance with some very special qualities.

Plenty of you, I'm sure, will disagree.