The two women were given wildcard positions reserved for players in the top 20 in the WTA rankings that don't originally enter an event.
"We're thrilled that Victoria and Marion have decided to play here in Toronto," tournament director Karl Hale said in a statement. "With them added to the list, we now have the best WTA player field in the world outside of the Grand Slams and mandatory events."
The addition of Azarenka and world No. 7 Bartoli means the Rogers Cup will feature all of the top 20 players in the WTA.