For the first time since introducing its anti-doping policy last July, the UFC has elected to waive a required four-month drug testing window for an athlete coming out of retirement.

Yahoo! Sports reported earlier this week that former heavyweight champion Brock Lesnar (5-3) had received this necessary exemption. Lesnar has not fought in the UFC since 2011 and officially retired last year, but recently signed up to fight Mark Hunt at UFC 200 on July 9, in Las Vegas.

According to UFC policy, which is enforced by the United States Anti-Doping Agency (USADA), "an athlete who has ceased to have a contractual relationship with the UFC, may not resume competing in UFC bouts until he/she has given UFC written notice of his/her intent to resume competing and has made him/herself available for testing for a period of four months before returning to competition."

Within that same article, however, the policy states, "UFC may grant an exemption to the four-month written notice rule in exceptional circumstances or where the strict application of that rule would be manifestly unfair to an athlete."

In a statement released to the press, the UFC confirmed Lesnar's exemption and stated he was added to the USADA testing pool on June 6. According to the statement, the UFC felt that since "Lesnar last competed on December 30, 2011, long before the UFC Anti-Doping policy went into effect, for purposes of the Anti-Doping policy, he is being treated similarly to a new athlete coming into the organization."

That is a fair assessment, as a UFC official confirmed to ESPN.com that a new athlete signing with the UFC for the first time is not required to meet the same four-month testing window as an athlete coming out of retirement. Under the program, once an athlete signs a contract, he/she is then immediately entered into the USADA testing program, which has conducted 859 total tests this year according to the USADA website.

The UFC went on to state that Lesnar was not added to the testing pool prior to June 6, because he only "agreed to terms and signed a bout agreement [on June 3]."

The UFC's ability to grant an exemption pertaining to previously retired athletes came up earlier this year, when featherweight champion Conor McGregor announced his early retirement from the sport in a post on social media. McGregor made it clear two days later he was not retiring, but there was some confusion, which was fueled by comments made by UFC president Dana White, regarding what effect the four-month testing requirement would have on his reinstatement.

Ultimately, McGregor never informed the UFC of his retirement in writing and it became a moot point. The first athlete to ever receive an exemption under this article of the policy, however, is now and forever will be Lesnar.