Mikel Arteta's £21 million Arsenal mistake is coming back to haunt him

With Arsenal stuttering in the Premier League title race, Mikel Arteta might be starting to regret his decision to allow one of his key players to leave the club last summer.

The Gunners topped the Premier League table for much of last season, but ultimately were unable to stop Manchester City from winning a third-straight league crown.

This season Arteta's side began the campaign among the favourites, but a string of poor results over the last few weeks has seen them fall five points behind league leaders Liverpool and drop out of the FA Cup.

Part of Arsenal's struggles stem from midfield, an area of the pitch they were particularly strong in last season.

Last term Arsenal's midfield was anchored by Thomas Partey, with Martin Odegaard and Granit Xhaka playing either side of him in the number eight roles.

Xhaka left the club last summer after seven eventful seasons at the Emirates Stadium, joining Bundesliga side Bayer Leverkusen in a £21 million move.

Xhaka was not always a key player in North London; he looked certain to leave the club in 2019 after he fell out with teammates and Arsenal fans.

However, last season he impressed as a left-sided number eight, scoring seven goals and providing seven assists in 37 league outings.

The near ever-present midfielder didn't just influence games through his own direct contributions, but by also linking up well with Gabriel Martinelli and creating space for the Brazilian winger to flourish on the left flank.

Though he is yet to make any league goal contributions for Leverkusen, Xhaka has hardly missed a minute for the side that currently sits above Bayern Munich at the top of the Bundesliga table.

Xhaka appeared to be saying his goodbyes at the weekend. Image: Alamy

Xhaka's departure forced Arteta into a rethink, and in truth he hasn't settled on a perfect replacement. £105 million summer arrival Declan Rice has performed the 'Xhaka role' at times this season, along with Leandro Trossard and Emile Smith Rowe.

One data set on Twitter shows that without Xhaka, Arsenal's ball progression has regressed.

To be fair to Arteta and Arsenal, Xhaka felt that the time was right to leave the club.

"The fact is that as a person I am always interested in new challenges," the Switzerland international said.

"After seven years, the time has come for something completely new. The league is not new, but the club is. During the talks with Simon Rolfes [Leverkusen sporting director] and Xabi Alonso, I felt that the long-term project at Leverkusen was worthwhile and that it was 100% in line with me."

Arteta isn't the kind of coach to stop players leaving if they want to, but given his side's current struggles, there's likely a part of him that wishes he'd done more to persuade Xhaka to stay.