Both players are expected to leave their respective clubs in the current transfer window and **Standard Sport** understands that Chelsea and United are currently exploring the logistics of a possible move that would see them head in opposite directions this summer.
Nkunku’s future at Stamford Bridge has long been subject to doubt after he started only nine Premier League matches under Enzo Maresca this season, scoring three goals.
The French international was a regular for Chelsea in the domestic cups and Conference League, notching 14 times in 43 total appearances across all competitions, though missed the semi-finals of the Conference League through injury and was an unused substitute in the final.
Bayern Munich were believed to be long-term suitors for Nkunku, with Juventus among the many other clubs linked with his signature to date.
United were also said to be considering an approach for the former RB Leipzig forward last summer, though are not believed to have formalised their interest at that stage.
The Red Devils remain on the lookout for significant attacking reinforcements under Ruben Amorim this summer having already [clinched the £62.5million signing](/sport/football/man-utd-sign-matheus-cunha-wolves-b1230687.html) of Brazilian forward Matheus Cunha from Wolves.
United are also now said to have submitted an improved second offer for Brentford talisman Bryan Mbeumo worth in excess of £60m, though missed out to Chelsea on a £30m move for Ipswich striker Liam Delap.
Similarly to Nkunku and United, Garnacho was a player of interest to Chelsea last summer when it appeared that he could leave Old Trafford, with more rumours in January as Serie A champions Napoli also pursued a deal.
United kept hold of the Argentine, though he is now expected to depart having publicly expressed his unhappiness with his substitute role in the Europa League final defeat by Tottenham in Bilbao and reportedly been told subsequently by Amorim in no uncertain terms to find a new club this summer.
Rashford is another player expected to leave United before the second summer transfer deadline in September having been frozen out by Amorim and then spent the second half of the season on loan at Villa Park.
Amorim appears keen to overhaul his squad after his first campaign at the helm resulted in the worst finish in the club’s Premier League history, eventually placing 15th in addition to losing the Europa League final to fellow top-flight strugglers Spurs, who finished 17th.