Chelsea have been monitoring France international defender Jonathan Clauss and are willing to sign him this summer if certain criteria are met.
The 29-year-old has been valued at around £10 million ($12m) by Lens, who recognise the defender has less than a year left on his contract and that he is unwilling to renew his deal.
One potential issue for Chelsea is the rival interest coming from Atletico Madrid, who have identified Clauss as a replacement for Olympiacos-bound Sime Vrsaljko.
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Will Chelsea sign Clauss & why do they want him?
Chelsea have space to add Clauss to their squad, with Antonio Rudiger and Andreas Christensen having left on free transfers to Real Madrid and Barcelona respectively.
Sevilla's Jules Kounde remains the club's primary target but the Blues could accelerate a deal for Clauss as soon as Cesar Azpilicueta's future is resolved.
Barcelona still want to sign Chelsea's captain, who has one year left on his current deal, and have been in negotiations about a nominal fee. Indeed, the Blues would have been happy to bow to the Spaniard's wishes and allow him to leave, given his legendary status in west London.
However, that agreement has been made through transfer chief Marina Granovskaia, who is now expected to leave the club soon, so it remains to be seen if the transfer will go through.
As well as impacting that agreement, the situation has also slowed Chelsea's activity regarding incoming signings. As well as Kounde, Chicago Fire's Gabriel Slonina was also close to completion but is now expected to stall.
In regards to Clauss, Chelsea have completed full due diligence, scouting his last 50 matches and having identified him as a target shortly after Thomas Tuchel joined the club.
He currently plays in a similar system at Lens, has amassed almost 100 games at wing-back and was on Chelsea's shortlist last summer when they tried to sign Achraf Hakimi from Inter, ultimately losing out to PSG.
In an interview with RMC Sport in May, Clauss spoke about how he grew up supporting Chelsea: "Since I was a kid, It’s Chelsea and it remains Chelsea [the team I dream about playing for]."
Chelsea view Reece James as the future of their right wing-back position and would bring in Clauss as a competitive back-up option.
It could, however, block the pathway of talented academy player Dujon Sterling, who did well on loan at Blackpool in the Championship.
Who is Chelsea target Jonathan Clauss?
Clauss failed to make the grade at his native Strasbourg during his academy days.
Ever since, the defender has been battling to prove himself, working his way up from the lower leagues back to Ligue 1.
After two seasons in Germany, where he won Bundesliga 2 and learned the language, Clauss signed for Lens.
It is there where Clauss has had the platform to prove himself and he has made the Ligue 1 team of the season two years in a row.
He made his debut for France in 2022 after this late-career ascent and is expected to be part of his country's World Cup squad under Didier Deschamps.