The Lisbon club, who announced Everton Soares, Jan Vertonghen and Luca Waldschmidt on Friday, are still looking to add new faces.
Edinson Cavani is closer and closer to a Benfica move and he could be joined by Joao Mario.
Di Marzio reports that Benfica have started talks with Inter to discuss a deal for the 27-year-old central midfielder.
Head coach Jorge Jesus likes Mario and worked with him at Sporting CP in 2015 and 2016.
Mario spent last season on loan at Lokomotiv Moscow, but the Russians did not use their option to buy.
The 45-time Portuguese international also had a loan spell with West Ham in 2018.
A return to Portugal could be on the cards though, if Benfica can strike a deal with Inter.