It was the first open session the Bombers have held since the supplements scandal broke more than a week ago.
Australian Sports Anti-Doping Authority testers wearing white polo shirts and carrying black clipboards approached individual players for tests as they left the track.
It's understood ASADA was conducting routine tests and it was nothing out of the ordinary.
The Bombers play Collingwood and the Western Bulldogs in the opening round of the NAB Cup on Friday.
ASADA testers were also spotted at Whitten Oval Thursday morning.
