Speaking ahead of Chelsea's Premier League clash with rivals United, Tuchel explained that during his time as PSG head coach from 2018 to late 2020, the Ligue 1 champions tried to lure Fernandes to Paris.
The Portugal international was captain of Sporting CP at the time, but eventually signed for United in January 2020 and has since scored 34 goals in 60 appearances across all competitions.
"With my first sporting director in Paris, Antero Henrique, a Portuguese sporting director, and he knew [Fernandes] very well," Tuchel told reporters.
"We fought hard to have a connection to him and to bring him to our team. I got made aware of him more in detail, so we watched more and more games about him and followed him and tried to be in touch with him to make it happen. Obviously, he decided [to sign for Manchester United]".