Garner spent last season on loan at the City Ground, where he played a key role in helping Nottingham Forest earn promotion back into the Premier League.
The Tricky Trees want to take Garner back to Nottinghamshire, while his immediate future at Old Trafford has remained under the scanner.
New Manchester United boss Erik ten Hag is keen on bolstering his midfield and Frenkie de Jong has been one of their top targets this summer, but he is looking more likely to join Chelsea, should he leave Barcelona this summer.
The Red Devils have also been working on a deal to snap up Rabiot from Juventus, agreeing on a £15m fee with them, but are yet to see eye to eye on personal terms with the player.
And Manchester United are tipped to decide whether to send Garner away on loan or keep him at the club once they are done with their efforts to secure the services of Rabiot.
Nottingham Forest have kept tabs on Garner’s situation at Old Trafford throughout the ongoing window but will only learn what Manchester United want to do with him after a deal to sign Rabiot is resolved.
It remains to be seen whether Manchester United get their man and allow Garner to earn regular game time at another club this season.
