It’s finally here. After years of speculation and anticipation, the moment every combat sports fan has been waiting for is just a day away: Ronda Rousey and Gina Carano will finally step into the ring this Saturday. But before they can throw a single punch, they have to get through one of the most nerve-wracking rituals in all of sports—weigh-in day.

This Friday, May 15, both legends will face their final pre-fight hurdle at the scales in Los Angeles. For Rousey, 39, and Carano, 44, it’s a moment that carries a unique weight: combined, it’s been 26 years since either of them last weighed in for an MMA fight. That’s a long time away from the grind of cutting pounds, and it adds an extra layer of drama to an already historic event.

Here’s what you need to know to follow all the action on Friday. There are actually two separate weigh-ins scheduled, each serving a very different purpose. The first is the official weigh-in, which kicks off at 12 p.m. ET and can run for up to two hours. During this session, all 22 fighters on Saturday’s massive card—including the main event and co-main stars like Nate Diaz—will step on the scale to make their contracted weight.

For Rousey and Carano, the target is 146 pounds for their non-title featherweight bout. If either fighter comes in over that mark, they’ll get a one-hour grace period to shed the extra weight and try again. Miss it a second time, and they’ll face fines and potential penalties depending on how far off they are. Once they hit the mark, though, the real work begins: rehydrating and refueling to regain as much weight as possible before fight night.

Then, at 9 p.m. ET, the show really begins. The ceremonial weigh-ins are less about the scale and more about the spectacle. Since everyone has already made weight, this is the moment for fighters to share one last intense faceoff in front of a packed crowd at Los Angeles’ Intuit Dome Outdoor Plaza. Expect final pre-fight remarks, a few tense stares, and the official kickoff to fight weekend. It’s the perfect appetizer for what promises to be an unforgettable main event.

Whether you’re a die-hard fan or just tuning in for the history, Friday’s weigh-ins are your first chance to see these two icons face off for real. Get ready—because after this, there’s no turning back.