Nick Diaz is becoming an itch Georges St-Pierre can't seem to scratch.

Looking back on his UFC 158 loss to St-Pierre, the candid welterweight star isn't happy with the Quebec athletic commission's handling of the bout.

In fact, MMAFighting.com recently received an email from Jonathan Tweedale, a Diaz camp representative, claiming an official complaint will be filed regarding the administration of St-Pierre's post-fight drug test:

Further serious irregularities including, inter alia, the Quebec Commission's failure to supervise fighters' provision of samples in connection with testing for Prohibited Substances and Prohibited Methods (under sections 71.1 to 71.6 of the Regulation), will be set out in an official complaint that will be filed imminently.

Let the conspiracy theories begin.

Some will undoubtedly chalk this up as Diaz expressing sour grapes over a loss, but these accusations remain consistent with things he has said in the past regarding St-Pierre.

During the week of the fight, Diaz made an appearance on Toronto's Fan 590 (via BloodyElbow.com), where he accused St-Pierre of using "steroids" and the athletic commission of turning a blind eye.

He doesn't believe anyone is actually standing over St-Pierre monitoring his tests.

Along with the drug-test issues, the Diaz camp is also upset with the weigh-in rule adopted by the commission. On Tuesday, MMAFighting.com was informed by a commission representative stating decimals were not counted at the official weigh-ins for the championship bout.

Typically, fighters are expected to weigh in exactly on the mark or under to qualify for a UFC title bout, but the rules implied by the Quebec commission are different.

Both St-Pierre and Diaz could weigh in at 170.9 pounds and still be cleared to compete for the UFC title.

Tweedale argues that the commission's rules bypass the original bout agreement signed by both fighters:

Section 168 of the Regulation respecting combat sports provides that the maximum weight that a fighter must achieve at the official weigh-in shall be determined in advance by contract - and if the fighter does not make the contracted weight - in this case 170 pounds - then 20% of his purse or "the contestant's remuneration" will be deducted and paid to his opponent (subsections (7) and (8)). The contracted weight for this fight was 170 pounds. 170.9 is not 170, anywhere in the world, for a title fight. There is no question what "170 pounds" means, in the bout agreement, as a matter of contractual interpretation.

Unfortunately for Diaz, the Quebec commission's rule to exclude decimals has been ongoing for the past five UFC events held in Montreal. This wasn't something thrown together overnight.

UFC 83 was the only event without the current rules in place. Instead of excluding decimals altogether, every fighter's weight was rounded off to the nearest half-pound.

With this complaint, the Diaz camp hopes to stir up enough controversy to warrant an immediate rematch, and they don't plan on budging until St-Pierre either accepts or vacates the welterweight title:

"In the circumstances, Mr. St-Pierre remains legally and ethically obligated to fight Mr. Diaz at 170 pounds or else vacate the belt in favor of those prepared to fight at welterweight."

Tweedale is a Vancouver lawyer whose only affiliation is with Nick Diaz. He does not rep Cesar Gracie or anyone else on his team.