Giovinco, 30, left Juventus for Toronto in 2015 and has scored 45 times in 72 appearances during a successful spell with the Canadian outfit.
The 23-time Italian international has claimed that Barcelona wanted to keep him in European football, but the presence of Lionel Messi, Neymar and Luis Suarez would have made it impossible to get a game.
"It's true that in the past there was interest from Barcelona but I would have been a ball boy there," Giovinco told reporters. "With the three stars they have in attack, I would not have played at all. I wasn't interested because I want to play.
"Neymar, Messi and Suarez could have played with one leg and still have an impact, so there was no sense in going there."
Giovinco, who played more than 130 times for Juventus between 2006 and 2015, managed 22 goals in 37 appearances for Toronto last season.