Wirtz has developed into one of the best playmakers in world football, the Germany international starring last season as Leverkusen put together an unbeaten Bundesliga campaign to dethrone Bayern Munich.
A total of 47 goals and 51 assists have been recorded during his 162 appearances, the target currently to retain the league title with Leverkusen and go as far as possible in the Champions League.
However, despite Wirtz being just 21 years of age and playing for the German champions, there is an acceptance that he will eventually depart for a bigger club.
Teams in the Premier League and La Liga have been heavily linked with his signature, including Manchester City, Liverpool and Real Madrid.
As it stands, it remains to be seen whether any of those teams will be prepared to pay at least £80m next summer in order to get a deal over the line.
Wirtz replacement identified?
Nevertheless, Leverkusen are in a position where they need to consider potential alternatives with Wirtz's contract due to expire in 2027 and a renewal far from a guarantee.
According to Fichajes, Leverkusen officials have placed Real Madrid man Brahim Diaz towards the top of their shortlist.
The 25-year-old has spent the bulk of his career either at Los Blancos or AC Milan, his prolonged loan stint at the latter proving key in his development.
As it stands, though, Diaz is viewed as a squad member at the Bernabeu with two starts and four substitute outings being made in all competitions this season.
That is partly down to injury, yet Diaz had failed to play for more than 45 minutes before his last appearance versus Real Sociedad on September 14.
Is a deal plausible?
Leverkusen would likely bank on Real being prepared to cash in on a player like Diaz courtesy of the other attacking talent that is at Carlo Ancelotti's disposal.
Diaz also has a contract until 2027, realistically making next summer as Real's prime opportunity to generate his market value through a sale.
That said, it is highlighted that Ancelotti views Diaz as a trusted member of his squad. As many as 10 goals and eight assists came from 40 outings in La Liga and the Champions League in 2023-24.
Much may depend on how Diaz is integrated when he has recovered from a hamstring injury.