The England international has had a start to the season plagued with disciplinary issues, although on the pitch his form has continued to impress.
That has led to continued links with a Premier League return and Goal reports that Chelsea are ready to make a big push for the youngster.
But they are already putting plans in place, and are willing to spend more than the club record £72 million fee they splashed on Athletic Club goalkeeper Kepa Arrizabalaga last year to get their hands on Sancho.
Manchester United have been regularly linked with a move for the 19-year-old, but Chelsea hope their case can be aided by Sancho’s close friendship with some of their players, including Tammy Abraham and Callum Hudson-Odoi, as well as the fact that he’s from London.
The teenager is seen as crucial to Dortmund's title hopes this season, having scored five goals and notched seven assists in 11 Bundesliga games so far.
Sancho hasn’t given the impression that he is agitating for an exit midway through the season, and Dortmund will be reluctant to let one of their key players go with the title race still very much alive.
Lucien Favre’s side are currently fifth in the standings, but only five points off top spot in a congested Bundesliga table.
Sancho is likely to command a transfer fee higher than the €105 million Barcelona paid to sign Ousmane Dembele in 2017.
United are willing to fork out a fee of up to €140 million to secure his services, but their dismal league form could make it difficult to convince the player.
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