3. Chael Sonnen (3)
The first drug test that Sonnen flunked was after his original title fight with Anderson Silva. You can’t blame Chael for trying to gain a bit of an advantage on his opponent, and it almost helped him win the belt that night.
He would become the first drug test failure under the USADA program as well (unless you count Wanderlei fleeing the test as the first failure). He flunked a test while on set for the Ultimate Fighter Brazil, and promptly retired from MMA. 2 weeks after his retirement USADA announced Sonnen had failed a 3rd random drug test for human growth hormone. Fox Sports fired Sonnen after the 3rd failed test.
