Arsenal made a near-£90million transfer mistake with Serge Gnabry that they will be eager to avoid again as they face a similar situation with Folarin Balogun.
Gnabry was one of the highest-rated young players to emerge at the north London club during the latter years of Arsene Wenger's reign as manager.
However, an ill-fated loan with West Bromwich Albion and Tony Pulis, allied with limited first-team opportunities at Arsenal, placed doubts in the German's mind that a long-term role in the first team would become a reality if he stayed.
As such, Gnabry demanded that he be sold, and with a year remaining on his contract, Arsenal had no choice to agree so they could demand a transfer fee.
Gnabry was sold to Werder Bremen for around £5million in 2015. Just six years later, he is one of the highest-performing wingers in world football and worth almost 20 times that.
According to a study from the CIES Football Observatory, Gnabry is now worth €103.3m, which equates to just under £90m.
The study takes into account a player's performance, age, contract length, and future outlook to determine an overall price.
Among the big five European leagues, Marcus Rashford is the highest valued player, while Bukayo Saka, at €116.2m is Arsenal's highest-valued player.
And the Gnabry nightmare has been replicated with other young players. Donyell Malen is now performing brilliantly in the Netherlands.
Ismael Bennacer has been a first-team regular for AC Milan when fit and cost around £15m two years ago.
Arsenal are now looking to avoid another young player leaving on the cheap before potentially developing into a world-class star.
Balogun is in the final six months of his contract and could force his way out of the club at the end of the season.
The Under-23s captain has scored seven goals in 15 Premier League 2 games. He also scored two goals in 61 first-team minutes in the Europa League group stage.
The young striker is highly regarded at the club, with Mikel Arteta previously stating that he is eager to sign the 19-year-old to a new deal.
"I’m still very positive that Flo is going to stay with us and it’s what we’re trying to do as a club, and it’s what I’m trying to do as a manager," he said last month.
"As far as I know from last week, the player wants to be here, so I’m positive. I think he’s made some big progress in a few months."
Whether Balogun could ever become a Gnabry-level player or not is difficult to determine, but Arsenal would surely like to find out themselves than risk another £90m transfer mistake.
