Coman is currently in his sixth season with the Bundesliga giants, accumulating 39 goals and 48 assists from 188 appearances in all competitions.
His career has been plagued by multiple injuries, but he has stayed unscathed for most of the current campaign, which has brought the best out of him.
The 24-year-old has registered six goals and 13 assists for the European champions this term, and it is already his best-ever return in a single season.
Despite this, there has been speculation regarding his future, and a recent report from The Mail claimed that both United and the Blues are keeping tabs on him.
While the Red Devils’ link has been known for a while, Chelsea have recently joined the mix, and Plettenberg has claimed that the club hold a ‘great interest’ in Coman.
Coman will have two years remaining on his contract this summer, and Plettenberg insists that Bayern are still looking to commit the Frenchman to a fresh deal.
Coman ended the previous campaign on a high by scoring the winner in the Champions League final against Paris Saint-Germain.
He has carried over the form this term, and that has been key to keeping his starting spot with the competition from summer signing Leroy Sane.
Coman can play in both wing positions, but has mostly found his success operating from the left wing for club and country.
United have Marcus Rashford, Anthony Martial and Daniel James, who have all impressed from the left side of the attack.
Coman may not be an ideal option for them, but could be an upgrade on the opposite flank, where he has played 37 percent of his Bayern games.
The Blues, meanwhile, don’t desperately need a winger, but Coman could be a target if Christian Pulisic heads for the exit door.
As things stand, Bayern are still in a good position to keep hold of the Frenchman, and the onus will be on convincing him to extend his stay.
Coman recently turned down a contract extension with the club, but talks are likely to continue. He is currently valued at £49.5 million per Transfermarkt.
Stats from Transfermarkt.com