Chelsea have attempted to secure an advantage in the race to sign Christopher Nkunku from RB Leipzig by arranging for the striker to undergo medical tests ahead of a proposed move, sources have told ESPN.

Nkunku, 24, has attracted interest from several top clubs, including Manchester United, Real Madrid and Bayern Munich.

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But Chelsea have attempted to position themselves at the front of the queue after overseeing private tests in Frankfurt a few weeks ago with a Chelsea orthopaedist present.

When asked for comment by ESPN, sources close to Nkunku insisted there was no agreement with Chelsea, or any other club, and any medical checks were routine for all players at the club.

Reports of the test first appeared in German newspaper Bild and have since been confirmed to ESPN by sources.

Nkunku is believed to have a release clause in his contract set at €60 million that comes into effect in the summer of 2023.

Chelsea have indicated a willingness to meet that price, but no deal has yet been reached given other clubs are interested and the clause is not yet in effect.

Nkunku has scored six goals in 11 appearances this campaign, building on last season's impressive tally of 35 goals in 52 games across all competitions.

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The France international can play as a centre-forward, a second striker or an attacking midfielder. Co-owners Todd Boehly and Clearlake Capital are keen on pursuing a transfer strategy involving acquiring younger players committed to long-term contracts and have identified Nkunku as a target.

Sources have told ESPN that Chelsea were keen on signing Nkunku this summer but that Leipzig wanted to keep him for another season and agreed a two-year contract extension with the player to 2026.