Arsenal has a glorious history in European football and is one of the real clubs on the continent at the beginning of the 21st century. Some of the best players in the world have come here, both in Highbury and at the Emirates Stadium. While the Gunners have historically not been the most willing players in the transfer market to spend money, there are many deals involving some top players, and the club hasn't always been able to do that. A number of star transfer deals that have grown into top players at Arsenal have also been completed, and the club has made a number of mistakes in the process.
Emiliano Martinez (£17m, Aston Villa, 2020)
Martinez was given a first-team chance in 2020 when Leno was injured after bouncing back in the Premier League. The Argentine performed well at the end of the Season for the Gunners, playing a major role in Arteta's side winning the FA Cup final and the subsequent Community Shield match. A few weeks after the Community Shield cup, he was allowed to travel to Aston Villa and was surprised to pay a minimum fee of around £15.6 million. Ramsdale signed for almost twice the money they earned for Martinez, which makes the deal all the more curious, especially given Martinez's outstanding debut season at Villa Park.
Sanchez (SwapMkhitaryan, Manchester United, 2018)
Sanchez was almost impossible to replicate when he was at Arsenal. Joining from Barcelona in 2014, the Chilean has been excellent on the left wing and Arsenal are as close to the league title as they have in the past. But problems remained and Arsenal never finished the title, so Sanchez saw an opportunity to continue looking for a team he thought was closer to success. Sanchez's performance at Manchester United has also proved to be unsatisfactory, but Mkhitaryan encountered a similar situation with Sanchez on the way to the transfer, and he is far from the level of Sanchez. It was a grave mistake to let Sanchez go to Manchester United, which brought Arsene Wenger to blame, and since his departure, Arsenal are no longer the same team they used to be.
Gnabry (£4.5 million, Bremen, 2016)
In hindsight, Gnabry's talent wasn't well developed at the Gunners, which was a huge mistake from Arsenal's perspective. Gnabry had few chances at Arsenal and played just 10 games in the Premier League before coming to West Brom on loan. In 2016, the Gunners sold Gnabry to Werder Bremen for a meager price of £4.5 million, and after scoring 11 goals in the Bundesliga, he moved to Bayern Munich 12 months later. He has become a Champions League winner, three-time Bundesliga champion and a mainstay of the German national team, which has left Arsenal remorseful for his premature abandonment.
Van Persie (£24m, Manchester United, 2012)
While it was the last trade Arsenal wanted to make, Robin Van Persie made it very clear in the summer of 2012 that he wanted to move to challenge for the league title. Much to the annoyance of the Gunners' loyal fans, Robin van Persie moved to Sir Alex Ferguson's Manchester United team and did have a Premier League title medal hanging around his neck at the end of the season. Arsenal replaced the Dutchman with Giroud, who, while outstanding, has begun to enter a trough since seeing the captain choose to leave one after another.
Nasri (£25m, Manchester City, 2011)
Nasri became one of the best players in the league at Arsenal, but with the Gunners still unable to shake off the embarrassment of not having a title at the time, the Frenchman chose to win elsewhere. In the summer of 2011, Arsenal were forced to sell Nasri to Manchester City for around £25 million, and a season later he won the Premier League title. Arsenal's left-back Crich also sold to Manchester City at the same window, another example of the club strengthening their Premier League opponents with limited chances of winning the title. It was a deal that could be beyond the club's control, but was still seen as a huge mistake.
Fabregas (£30 million, Barcelona, 2011)
The summer of 2011 was a painful transfer window for Arsenal, and the most painful was Fabregas losing their captain and star midfielder after returning to Barcelona. The deal marked the beginning of the Gunners' buying of captains and home stars, with star players leaving to look elsewhere for better opportunities, all at relatively low sums. Fabregas is an integral member of Wenger's squad, and together they have any chance of winning a trophy, and letting him leave so easily was one of the biggest transfer blunders in the club's history. To make matters worse, Fabregas will return to the Premier League after three years and play a central role for arch-rivals Chelsea, winning two Premier League titles with the Blues.
Henry (£16 million, Barcelona, 2007)
Henry is still arguably the greatest player in Premier League history, having been allowed to move to Barcelona in 2007 with a huge mistake by Arsenal. Henry brought Arsenal two Premier League titles and took them to the Champions League final, but a move to Barcelona was inevitable as he pursued the next step in his career. The Frenchman won two La Liga titles and the coveted Champions League, which justified his transfer, but the Arsenal deal was a major mistake.
Ashley Cole (Gala + £5m, Chelsea, 2006)
Arsenal fans have never really forgiven Ashley Cole's move to Chelsea as the left-back defected to the Gunners' rivals. The deal was made worse by the lowest transfer fee and the exchange of a player four years older than Cole, who never really got back his best form at the Emirates Stadium. Cole has won another league title at the Blues and won the Champions League title in 2012, while the topic of selling Cole remains a sensitive topic for Arsenal fans.
Vieira (£18m, Juventus, 2005)
This sale is probably the most bizarre on the list. At the age of 29, Patrick Vieira still maintained a high level of competitive form, and from 1999 to 2004, he was named to the PFA Team of the Year every year. But curiously, the Frenchman was allowed to join Juventus in 2005 and was replaced by the very young Alexander Song, which proved to be a huge mistake for Arsenal. Vieira spent only one year with the old woman, but that was because he moved to Inter Milan, where he won four consecutive Serie A titles and the 2010 Champions League title.
Andy Cole (£1.35 million, Bristol City, 1992)
Perhaps the most legendary deal on the list, Arsenal took the 20-year-old Andy Cole out of their ranks in 1992 without even a single Premier League appearance. Cole was sold to Bristol City for £1.35m and travelled to Newcastle United the following year, where he scored a staggering 34 goals in his first season in the Premier League. Cole scored 187 goals in the English top flight and has been occupying second place in the Premier League's all-time top scorer list until he was overtaken by Wayne Rooney. Cole appears to have pioneered the trend of turning out players winning trophies outside arsenal, having lifted the Premier League Champions Cup five times and won the Champions League with Manchester United.