There was a time when Manchester United wingers struck fear into the hearts of their opponents.
Players like Cristiano Ronaldo, Ryan Giggs, David Beckham, Andrei Kanchelskis and, at his best, Lee Sharpe (Ralph Milne can probably leave the room at this point). Players capable of tearing teams apart with raw speed, a moment of sublime skill or the accuracy and trajectory of a ball delivered from the flanks.
It has become a hallmark of Sir Alex Ferguson's success at Old Trafford down the years. But no more. Giggs is still gracing the Premier League stage, but partly because he has reinvented himself as a more rounded footballer who can also operate in the middle of the park or tucked in behind the striker where he can use his reading of the game and ability to spot and execute a killer pass to maximum effect. Though far from slow at the age of 35, he is no longer the winger who burst onto the scene as a teenager 18 years ago.
That job now falls to the likes of Nani, Antonio Valencia and Park Ji-sung, and would you honestly pick any one of them ahead of their predecessors in a red shirt?
Picture Peter Schmeichel's monster throws releasing Kanchelskis on a lightning counter-attack, Beckham putting it on a plate for Ruud van Nistelrooy, or Ronaldo and Giggs almost single-handedly turning a game, and then ask yourself whether the class of 2009 are capable of doing the same on a regular basis; whether they have the same wow factor.
It is an issue that has so far been largely overlooked at United because Ferguson has more pressing problems elsewhere in his team. The alarmingly bad form of goalkeeper Ben Foster this season has raised serious doubts over his claims to succeed the ageing Edwin van der Sar at United, never mind becoming England's new No.1.
The defensive lapses that have undermined the previously impregnable defensive partnership between Rio Ferdinand and Nemanja Vidic is another worry, as are concerns that the champions lack the quality in midfield to rival the likes of Frank Lampard or Cesc Fabregas.
Ferguson's high-octane attack is no longer what it used to be, either, with an over-reliance on Wayne Rooney and continuing fears that the enigmatic Dimitar Berbatov and hired gun Michael Owen do not compensate for the loss of Ronaldo and Carlos Tevez.
That relies in part on the service they get from the wings, and there is little doubt United also are weaker in this department as well. Indeed, when Nani announced in June that he was the man to step into Ronaldo's shoes, you could almost hear the laughter all the way from Old Trafford to Lisbon.
Some would suggest that, on current form, the comparisons between the two men start and end with the fact they are both Portuguese and can usually be found playing on the wing. That may seem harsh on Nani but there is little doubt that instead of stepping up to replace the World Player of the Year following his £80 million move to Real Madrid, he has actually taken a significant step backwards this season.
Over-elaborate and ineffective, he is guilty of often choosing the wrong option and taking five touches when one would suffice - in fact, everything a teenage Ronaldo was doing before United's coaching staff got hold of him, so maybe there is hope for his compatriot yet.
Nani's shortcomings were painfully evident at Stoke last month when he was hooked by Ferguson just ten minutes into the second half after an infuriatingly inept display that brought a chorus of "you'll never be Ronaldo" from the home fans, and probably a few United supporters as well.
His replacement, the evergreen Giggs, came on to turn the game by setting up both United's goals, the first with a simple square ball to Berbatov that only demonstrated where Nani had been going wrong. It came just a week after Giggs' sublime pass had played in Owen to win the Manchester derby. Moments of brilliance like these - not the occasional long-range goal or head-over-heels celebration - show real star quality, and few would dispute that Nani has failed to progress from the young player who showed such potential two years ago.
Of course any United winger is likely to suffer by comparison with Ronaldo and Giggs, arguably the two greatest wide players in the history of the Premier League, not to mention Beckham and Kanchelskis in his Old Trafford pomp or, for those with longer memories, the great George Best. But can you honestly say Park is a player to set the pulse racing?
Often selected by Ferguson in games against United's Big Four rivals in recent years, the South Korean has been used sparingly this season despite signing a new contract last month.
With the roving Ronaldo in full flow all over the field, in the past Park could be deployed as an effective counterweight. He was a player who was more than happy to track back and get a foot in; the roundhead to complement United's resident cavalier. With Ronaldo long gone, he just looks plain ordinary and a record of 12 goals in more than four seasons at United hardly marks him out as a major threat to the opposition.
As for Valencia, some would say it is too early to judge, and they may be right. However, let us not forget that we are talking here about an £18 million acquisition who had already made his name in the Premier League and found his way onto Real Madrid's radar, not a minor investment for the future.
Even his old supporters at Wigan would accept that Valencia lacks the panache of many great wingers, and there have been few signs so far that he is going to set the world alight in a United shirt.
Of course, Ferguson signed another young player capable of operating on the wing last summer, and in Gabriel Obertan we really do have something of an unknown quantity. Reports from Carrington indicate that Obertan may finally be ready to make his debut after arriving from Bordeaux with a back injury.
Ironically, the last young French winger/forward that Ferguson signed in the hope of turning him into the next Thierry Henry can be found in a Bordeaux shirt these days. And if proof were required that he doesn't always get it right, we need only look at David Bellion.