The Athletic have claimed that the deal is subject to a medical and that Forest will be paying Henderson's full salary for the duration of his stay at the City Ground.
Henderson enjoyed an incredibly successful two-year loan spell at Sheffield United. In the first season (2018-19), he played 46 league games, keeping 21 clean sheets and helping the Blades win automatic promotion.
His second season (2019-20) included 36 appearances back in the Premier League, where he kept 13 clean sheets, helping the team finish an impressive ninth in the league table.
The shot-stopper then returned to Old Trafford and signed a new five-year contract. He had hopes of becoming the new Manchester United number one, as well as replacing Jordan Pickford as England's first-choice keeper.
However, David de Gea's career revival has limited Henderson's game time at the Red Devils to the point where he failed to make a single Premier League appearance last term. The 25-year-old fell out of contention for a spot in Gareth Southgate's Three Lions side in the process.
Henderson looks set to replace the immensely popular Brice Samba. The Congolese has told the newly promoted side that he will not sign a new contract and wants to leave the club this summer. He is expected to join Ligue 1 side RC Lens subject to an agreement over a transfer fee.
Samba was a key part of Forest's first promotion back to the Premier League for the first time since 1999. Henderson will have some mighty big boots to fill at the East Midlands club.
Manchester United reportedly target Championship goalkeeper to replace Dean Henderson
Henderson's imminent departure would leave Erik ten Hag short in the goalkeeping department. 36-year-old Tom Heaton is the only other senior shot-stopper left at the club apart from De Gea.
According to GOAL, United are targeting Watford's Daniel Bachmann to become the club's backup goalkeeper. The report claims that the Hornets are seeking around £4 million for the Austrian international.
The 27-year-old played 12 times in the Premier League last season as Watford were ultimately relegated from the English top flight once again. He has also played 13 times for his country and started all of Austria's four games at Euro 2020 last year.
Bachmann believes he can become Manchester United's cup goalkeeper during the upcoming campaign. However, he will have to accept rare starts due to the excellence of De Gea over recent years.
The report also claims that Bachmann is one of a number of targets this summer, with Manchester United still yet to make a signing during the current window.
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