Bellator’s special attraction bout between Kimbo Slice and Ken Shamrock has been promised to fight fans, but it’s not a lock.

In order for this Bellator 138 main event to actually go down, both men must pass random drug screenings by the State of Missouri.

MMAFighting.com broke the news:

Missouri Office of Athletics director Tim Lueckenhoff told MMAFighting.com that both contestants will need to undergo “additional testing” and will, of course, need medical clearance before they are granted a license to compete in the state. Lueckenhoff, who is also the Association of Boxing Commissions (ABC) president, would not go into details about the tests, but Bellator confirmed that it would be similar to how Nevada and California have been testing out of competition. It is unknown if there will be blood and urine tests done or just urine.

Bellator 138 goes down on June 20 in St. Louis.

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