Real Madrid are among the clubs interested in signing Fenerbahce midfielder Arda Guler, but sources have told ESPN that the amount of commission being demanded on top of the €17.5 million ($19.1m) transfer fee is complicating the deal.

Madrid have been tracking Guler, who scored a stunning goal in Turkey's win over Wales last week, for a while.

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Sources have told ESPN that a €17.5m ($19.1m) release clause makes the 18-year-old an "attractive option" and he fits the Spanish club's strategy of investing heavily in the game's youngest talent.

In recent years, Real Madrid have signed Vinicius, Rodrygo, Eduardo Camavinga and Aurelien Tchouameni, with Jude Bellingham arriving this summer and young Brazil striker Endrick to follow when he turns 18.

However, sources added that doubts have emerged at the Bernabeu over Guler's prospective transfer because the commission being requested to complete the deal would make the fee "significantly" more than the €17.5m ($19.1m), which also includes a 20% cut of any future transfer fee for Fenerbahce.

That has forced clubs including Ajax, Borussia Dortmund, Sevilla and Liverpool to all take a step back from negotiations for now.

Madrid have not been ruled out of following through on their interest because the reports they have on Guler are extremely positive, but sources point out that Carlo Ancelotti's squad is well stocked in midfield.

Bellingham has been signed for €103m ($112.7m), while Luka Modric, Toni Kroos and Dani Ceballos have all renewed their contracts, with Camavinga, Tchouameni and Federico Valverde also competing for places in the middle of the pitch.

Therefore, Madrid can't promise Guler regular game time, which sources say the player will prioritise when picking his next destination.

Madrid's original idea was to place him at Castilla -- their reserve team who just missed out on promotion to the Spanish second division -- or loan him out.

However, sources have told ESPN that Guler would prefer to join a mid-level club to continue his development before making the next step in his career.

Sources added that joining Madrid is thought to be a dream move for Guler, who has supported the club since Mesut Ozil -- his idol growing up who he later had the chance to play alongside at Fenerbahce -- played in the Spanish capital.

RB Leipzig, AC Milan and Barcelona are also tracking Guler, but the Catalan club face similar problems to Madrid when convincing the player he would get regular game time.

Barca coach Xavi Hernandez has asked for a "Santi Cazorla-type player" this summer and Guler could fit that mould, but in addition to being unable to promise him minutes, Barca are also hamstrung financially.

They can only spend 40% of anything they raise due to LaLiga's financial fair play regulations.

The midfielder, meanwhile, would need to be convinced as he has other priorities, while renewing at Fenerbahce -- and increasing his release clause -- remains possible as well.

Guler, who made his senior debut in 2021 as a 16-year-old, made 35 appearances for Fenerbahce last season, scoring six goals in all competitions as they finished second in the Super Lig and won the Turkish Cup.