Lazio sporting director Igli Tare has acknowledged that, in hindsight, allowing Felipe Anderson to join Manchester United for EUR50million could have helped the club strengthen.
Tare revealed in January that Lazio had rejected a big-money offer from United for the Brazil international as they wanted to build on last season's success.
Lazio have been struggling to replicate last term's form, though, and Tare feels things may have panned out differently had they sold one of their stars.
"We have to make a complete analysis when making decisions, both on an economic and a sporting level," Tare told Corriere dello Sport.
"I have seen the transfer activity at other clubs, where they decided to sell some of their valuable assets. It happened at Juventus, at Roma, at Inter and at Napoli. Those could be examples for us.
"I can understand it if you sell a player and then reinvest the money to strengthen the squad. Maybe we made a mistake not to sell anyone.
"But the idea behind our decision not to take the EUR50m for Felipe Anderson was because we wanted to continue our project with the same group after a good season.
"If you make it into the Champions League, your players are worth even more."
Felipe Anderson has a contract with Lazio until June 2020.