Reports in the Metro
The 23-year-old has been linked with a move to United to for some time now, and if the reports are correct then they have got the jump on rivals Liverpool for his signature.
The Metro have cited ESPN Brazil reporter Jose Elias as the man to make the announcement, who has said that the fee of £13.1m has been agreed on by the two clubs.
Firmino acerta com o Manchester Uted valores da negociação 18 milhões de euros,com um Up no contrato da Adidas ficam atrás de Messi e Soares
— José Elias (@zeelias05) June 9, 2015
Red Devils boss Louis van Gaal is already off the mark in the transfer market as he looks to rebuild his squad ahead of a renewed title challenge for the Premier League.
Firmino linked up with Hoffenheim back in 2010, and has gone on to chalk up 151 appearances for the club, scoring 49 goals in the process.