The Ligue 2 champions have been extremely aggressive in the transfer market this summer, having agreed deals for Atletico Madrid's Radamel Falcao and Porto duo James Rodriguez and Joao Moutinho.
Chelsea were also in the hunt for Falcao, and they risk being beaten to the punch yet again as French newspaper L'Equipe suggests Hulk is Monaco's next top target.
The Zenit St Petersburg forward has failed to settle in Russia since his big-money move last year, and L'Equipe claim Monaco are willing to pay up to €45m to reunite him with Falcao, Rodriguez and Moutinho - his former-Porto teammates.
The 26-year-old forward managed seven goals in 18 league appearances for Zenit following his €40m move, but his high wages reportedly provoked a dressing room revolt.
One year out from a World Cup on home soil, Hulk wants to make sure his place in the Brazil starting lineup is guaranteed.
Chelsea have been strongly linked, but it remains to be seen whether Jose Mourinho would be willing to match Monaco's financial muscle.
A deal for Hulk would take Monaco's outlay past the €180m mark for four players this summer - Falcao, Moutinho, Rodriguez and the Brazilian forward - as they look to become a major player on the European scene.
Chelsea secured their first signing of the summer earlier this week, confirming an agreement with Bayer Leverkusen for the transfer of Germany forward Andre Schurrle.