Brooklyn Nets fans, at least the ones that attempt to be boisterous, will occasionally shout "BROOOOOOOOOOKKLYN" when things are going well for the home team, elongating the "O" to create a surround sound effect. Toronto Raptors fans like to mock the Nets in whatever way possible. Thus, during a Game 5 blowout, they mocked the chant while Amir Johnson was at the free-throw line.
In doing so, they sound ... exactly like Nets fans making the chant. Maybe the chant needs to be tinkered.