The former Borussia Dortmund man was expected to be the first name out of the Old Trafford door this summer, having seen his relationship with Erik ten Hag deteriorate last year.
Sancho had seemingly ended his own Man United career by hitting out at Ten Hag's explanation for his absence from a Premier League squad, as the Dutchman alleged that the winger had not been cutting the mustard in training.
After making an explosive social media statement and refusing to apologise, Sancho was ostracised from the group and allowed to re-join Dortmund on loan in January, helping the Bundesliga giants reach the Champions League final.
Upon his return to Manchester, Sancho and Ten Hag unexpectedly buried the hatchet, and the 24-year-old played a key role in Man United's pre-season preparations, often featuring up front due to Rasmus Hojlund's injury.
Man United 'internally expecting' Chelsea bid for Sancho
However, Sancho was then omitted from the squad for the Red Devils' opening Premier League win over Fulham, a telling sign that Ten Hag is not prepared to fully re-integrate him despite setting aside their differences.
With a permanent return to Dortmund not proving feasible, Paris Saint-Germain had emerged as the leading contenders to sign the 24-year-old, although the French champions are now thought to be prioritising a new striker due to Goncalo Ramos's injury.
Instead, The Athletic - via the Manchester Evening News - claims that Old Trafford chiefs are 'internally prepared' for Premier League counterparts Chelsea to come forward with a bid for Sancho before the transfer window slams shut on August 30.
Sancho's £250,000-a-week salary has proven to be the biggest stumbling block to a deal so far, but Chelsea will free up a significant chunk of their wage bill if the exiled Raheem Sterling leaves in the coming days.
The Blues will supposedly be quoted £40m to prise Sancho away from Man United, where he has only conjured up 12 goals and six assists from 83 competitive appearances since his £72.3m switch from Dortmund in 2021.
Do Chelsea really need to sign Sancho?
Leaving aside Sancho's underwhelming record in the Premier League and the expectation that Sterling will head for the exit door either this week or the next, the Man United attacker is surely the last thing that Chelsea need right now.
Despite Enzo Maresca's affirmations that he is only personally working with around 25 or 26 senior players, the fact that another 15 or so are still employed by the club and are being forced to train away from the main contingent is appalling.
When it comes to wide options, Chelsea have already strengthened in that regard this summer with the captures of Pedro Neto and Joao Felix, while Noni Madueke, Cole Palmer, Mykhaylo Mudryk, Christopher Nkunku and Angelo are also on the books.
Furthermore, a top-class centre-forward must surely be the Blues' priority between now and August 30, and the number nine shirt interestingly remains vacant in West London, suggesting that Chelsea are holding out for a big-money striker to arrive imminently.
While Sterling is all but guaranteed to leave and could very well be followed by Angelo and Madueke, Chelsea have enough options to cover out wide without paying over the odds for a man who has never found his feet in the Premier League.