All 13 fighters who were tapped to undergo drug testing at this past weekend's UFC 100 passed their tests.

Those undergoing tests were headliners Brock Lesnar and Frank Mir, co-headliners Georges St-Pierre and Thiago Alves, and undercard winners Jon Fitch, Dan Henderson, Yoshihiro Akiyama, Mark Coleman, Tom Lawlor, Jon Jones, Dong Hyun Kim, Jim Miller and Shannon Gugerty.

UFC 100, which featured a total of 11 fights, took place July 11 at the Mandalay Bay Events Center in Las Vegas and aired on pay-per-view.

All fighters were tested for drugs of abuse (such as marijuana and cocaine), as well as anabolic steroids and other performance-enhancers.

Although the NSAC had recently tested some fighters prior to Las Vegas-based events as part of its year-round drug testing initiative, no such tests were conducted for UFC 100.

The successful drug tests are another bit of good news for the UFC's milestone event. UFC 100 drew approximately 11,000 fans for an estimated $5.1 million gate, which would rank second in UFC history, and garnered a record number of credentialed media members. The event is also expected to do well over a million PPV "buys."