Chelsea youngster Andreas Christensen has made his way on to Barcelona's radar after emerging as one of the Premier League's top young talents.
The 21-year-old has pushed David Luiz out of the first team after the Brazilian endured a shocker against Roma in the Champions League, and Christensen has looked impressively assured in the Chelsea backline in recent weeks.
The Dane has missed the Blues' last two matches through a bout of illness, but should be restored to the starting XI by Antonio Conte for the upcoming game against Arsenal.
Barca are light in defence at the moment, with Samuel Umtiti a long term injury victim and Javier Mascherano set to depart the Nou Camp for China, and so they are rumoured to be keen to bring someone in in January - Manchester United defender Daley Blind has also been linked.
It is understood that Chelsea want to move quickly to offer Christensen a new deal in order to fend off interest from other clubs - his current deal runs until 2020.
It has been a good rise for the defender, who was signed by Chelsea in 2013 from Brondby, before being loaned out to Borussia Monchengladbach for experience.