Following being promoted to the Premier League, Nottingham Forest are eyeing making significant additions to the squad in order to survive in the top tier next season.
They have taken a liking to players in the Bundesliga and are closing in on a deal to sign Union Berlin striker Taiwo Awoniyi this summer, while they are also in talks for Mainz defender Moussa Niakhate.
More players from the Bundesliga are being assessed by Forest for other areas of the squad, including in midfield.
According to local German daily the Stuttgarter Nachrichten, the newly-promoted Premier League side are also interested in signing Mangala from Stuttgart.
Steve Cooper wants to add more steel to his midfield this summer ahead of their first season in the Premier League in 23 years.
The 24-year-old defensive midfielder has been assessed by the Nottingham Forest recruitment team and they are keen to take him to the City Ground.
He has two years left on his contract with Stuttgart and the club could sell him if they receive around €20m.
Nottingham Forest are also close to signing Manchester United goalkeeper Dean Henderson on loan this summer.
