If you used a Xebex rower for 18.1 last week, your score is now invalid. CrossFit announced Wednesday afternoon that the use of a Xebex rower violates the “uncommon movement clause” in the CrossFit Games rulebook.

Several athletes, notably Jacob Heppner, called out the issue on social media stating that the Xebex rowers counted calories significantly easier than its Concept2 counterpart. As the Concept2 rower has been the standard rowing machine since the inclusion of the rower in the Open, CrossFit believes any deviation from this standard gives the athlete an unfair advantage.

Athletes who used a Xebex rower must notify CrossFit at [email protected] by Monday, 5pm Pacific Time, the same time as the close of 18.2, in order to continue in the competition. Those who do notify will be assessed a major penalty of a 15% deduction.