It is expected that a deal could be finalised in the next ten days, with Gabriel linking up with his new club ahead of next season.
That's despite the fact the Brazilian is under contract with Lille until 2023 and has previously pledged his commitment to the Ligue 1 side.
Signed for just £1.5m from Avai in his native Brazil in 2017, Gabriel's stock has since risen significantly over the past three years.
The centre-back is part of a group of talented youngsters who have developed under sporting director Luis Campos and head coach Christophe Galtier.
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