History is repeating itself at Arsenal and it soon pose a problem for Mikel Arteta.
Ahead of the 2014/15 season - ironically when the Spaniard was officially named club captain - Mathieu Debuchy arrived from Newcastle United for a fee believed to be in the region of £12m.
The Frenchman was signed as a direct replacement for Bacary Sagna who had departed for Manchester City on a free transfer following seven years of service at the Emirates Stadium.
However, Debuchy's Arsenal career never got going.
He required ankle surgery a month into the new season, returned to action three months later before being ruled out for another three months in January 2015 and didn't make the FA Cup final squad.
Those two injury set-backs pretty much spelt the end for Debuchy in north London and once Hector Bellerin seized the opening at right-back, he never got an extended run in the side and following a couple of loan spells he returned to France permanently in January 2018.
Fast forward a couple of years and the emergence of Bukayo Saka could have an impact on Kieran Tierney's career at Arsenal.
The signs are eerily reminiscent of how Debuchy started life in the capital.
Tierney - a £25m summer signing from Celtic - was seen as the long-term replacement for Nacho Monreal (a fan favourite who spent six-and-a-half years at Arsenal) but has struggled to stay fit thus far.
After recovering from an hernia operation which saw him miss the first few weeks of this season, the Scotland international looked to have cemented is place as the first-choice left-back.
That was until he dislocated his shoulder in the 3-1 win over West Ham United in December. That was the exact same injury Debuchy suffered in January 2015 against Stoke City which effectively ended his Arsenal career.
This isn't to say Tierney will go the same way as Debuchy, but he will by no means be an automatic starter when he returns to full training - which could be as early as the end of the week.
Just like Bellerin in 2014/15, Saka is Arsenal's standout youngster this season and is getting better and better in a position that he's not completely sold on just yet.
"I feel like my dream was always to be a winger, to affect games, score goals and get assists," he said after the 4-0 win over Newcastle United. "For now I'll do the job the manager asks me to.
"In the future if I do get to go back onto the wing I feel like I know how full-backs play and playing as a full-back I know what wingers do, what I like them to do and what I don’t like them to do. It's a good learning experience for me."
But with 10 assists to his name this season and the way Arteta has him playing virtually as a winger - with the left-sided attacking tucking in - when in possession, there's no reason to suggest he can't make the left-back spot his own.
With that said, Tierney who has demonstrated brilliant crossing ability in his fleeting Arsenal appearances this season is likely to be given his chance to impress Arteta now that Sead Kolasinac could be out for a while.
Although Tierney's return means Arteta will soon have a problem with Saka. Does he keep him at left-back or push him forward again?
