Chelsea's 25-year-old centre-back Christensen's contract at Stamford Bridge expires at the end of the season. The players have yet to reach a deal with the club.
Christensen is getting the attention of Europe's big four, including Barca, Bayern, Atletico Madrid and Borussia Dortmund.
No one doubts Barca's interest in free agents, who have signed Depay, Garcia, Alves, Aubameyang and Aguero before retiring.
As Barcelona are struggling with financial problems, Camp Nou is paying more attention to the powerful players who are about to become free agents in terms of reinforcements. Chelsea's Danish centre-back Christensen is a great choice.
However, Bundesliga supremacy Bayern Munich may not allow Barcelona to sign the centre-back without any pressure. Bayern's demand for centre-back players is real.
The Bavarian giants have had trouble in the back line this season. And, with centre-back Nikolas Jules joining Borussia Dortmund at the end of the season, Bayern will undoubtedly introduce new blood in the centre-back position. If Christensen can't reach a deal with Chelsea, he will be a suitable target for the Bundesliga giants.
After Barca and Bayern, Atletico also want Chelsea centre-backs. This season, Atletico Madrid's defenders have been in poor form, conceding 12th in La Liga so far. Poor defense has even put into question coach simeone's coaching prospects at the Wanda Mets.
Atletico really need good defenders to come in and Christensen can be a big part of this La Liga powerhouse. And if you take into account the absence of a transfer fee, Christensen would be a good deal for Atletico to reinforce.
Unlike the above teams, Dortmund have always lacked big signings. Christensen's free transfer prospects are undoubtedly in line with the Hornets' transfer strategy.
Dortmund have already won Nikolas Jules from Bayern, a testament to the Hornets' ability to wrestle the wrists with other giants. If Borussia Dortmund can completely strengthen the back line this summer and then retain Haaland, then this team has the strength to shake Bayern Munich's hegemony in the Bundesliga.