According to a report from Sport1, a contract extension with Chelsea is not completely off the table, but it seems unlikely at this stage.
Apparently, Borussia Dortmund are keen on signing the 25-year-old on a free transfer, and it will be interesting to see if they can snap him up in the coming months.
The report adds that several other top clubs are involved in the transfer chase, and it remains to be seen where the 25-year-old ends up.
Christensen has done a reasonably good job under Thomas Tuchel, and he has the potential to develop into a top-class defender. The Danish international is highly rated at Stamford Bridge, and the Premier League side must do everything in their power to keep him at the club beyond this season.
If Dortmund manage to sign him on a free transfer, it would be a major transfer masterstroke from them.
The German Bundesliga club need to bring in quality young defenders, and Christensen could be a solid long term acquisition for them.
The 25-year-old is yet to reach his peak, and he will improve with regular first-team football and coaching. Dortmund could have a future star on their hands if they can lure him away from Stamford Bridge at the end of this season.
A January exit seems unlikely because Chelsea are still involved in the title race, and they will not want to weaken their side anytime soon.
Christensen is one of the three defenders who could leave Chelsea at the end of this season. The likes of Antonio Rudiger and Cesar Azpilicueta have been linked with moves away from Stamford Bridge as well.