Every club has endured missed opportunities in the transfer market over the years and Celtic are no different, with there being a plethora of star names whom the Parkhead outfit have missed out upon in the modern era.

One lesser-known story of what could have been is that of former United States international Brad Friedel, with the now-retired colossus having seemingly come close to joining the Premiership side almost 30 years ago.

As the story goes, the 82-cap goalkeeper was taken on trial by the Scottish giants in 1993, having endured difficulties in gaining a work permit with a handful of other British clubs.

Although there have been suggestions that then-manager Liam Brady was keen to sign the American, the more popular belief is that the club simply passed up the opportunity of a deal to sign the promising unknown quantity, with the likes of Packie Bonner and Gordon Marshall already on the books.

The 6 foot 3 menace would eventually spend time at the likes of Brondby, Galatasaray and Colombus Crew before returning to Britain in 1997 to join Liverpool, albeit while enduring a bit-part role at Anfield.

It wasn't until his subsequent switch to Blackburn Rovers in 2000 that the Ohio native truly began to make the Hoops pay for their blunder a few years earlier, as he went on to prove himself as a hugely dependable asset at Ewood Park.

He racked up 355 appearances during his eight-year stay at the Lancashire club, memorably scoring in a 3-2 defeat to Charlton Athletic in 2004, while he also ranks in the top ten goalkeepers for penalties saved (six) in Premier League history.

That haul was bolstered by his display against Sheffield United at Brammall Lane in 2006, as Friedel remarkably saved two penalties in the final 20 minutes, having previously been dubbed the "Human Wall" for his penalty-saving exploits at the 2002 World Cup.

Moves to Aston Villa and Tottenham Hotspur followed for the ever-reliable 'keeper, with his spell at Spurs seeing his record-breaking run of 310 consecutive league starts come to an end, stretching from 2004 until 2012.

That stunning record is no doubt a marker of just what a consistent figure the 51-year-old was for a number of years, with it testament to both his quality and his fitness that he was able to enjoy a career which spanned across three decades before his retirement in 2015.

While it would have been hard for Brady and co to envisage the American enjoying such success when he rocked up in Glasgow as a youngster all those years ago, it remains a real case of regret and what might have been for those at Celtic Park.