United made contact with the Seagulls earlier this week to enquire about the player and have since rushed the deal along.
Sky Sports state that not only has Baleba passed his medical, but he has signed a five-year contract with an option to extend until 2032 in what is a swift deal for the Red Devils.
Journalist Samuel Luckhurst has given an update on the deal on Monday morning, stating that United are due to announce him later today despite his current injury.
“#Mufc hoping to announce Carlos Baleba deal today. Paperwork being finalised, so Baleba set to be signed well before Friday 12pm deadline to make debut vs Ipswich - if he is considered fit enough after missing Brighton's August friendlies with an ankle injury.”
Baleba will join Youri Tielemans and Andrey Santos as midfield reinforcements with for manager Michael Carrick who is also reportedly chasing down Barcelona’s Alejandro Balde and Leicester City’s Louis Page.
Despite midfield reinforcements, United lost 2-0 to newly promoted Hull City on Saturday afternoon as they were overrun in the middle of the park.
Baleba will aim to help out the side but as he recovers from an ankle injury picked up during preseason, he could remain unavailable for United next clashes against Ipswich Town and Everton.
October has also been reported as a return for the midfielder, in what is worrying news for United fans keen to see their midfield take shape.