When Andy Ruiz Jr. knocked out Anthony Joshua in the seventh round to take his three heavyweight world title belts in a massive upset on June 1 in New York, few had given him a chance because of his chubby physique compared to the muscled Joshua.

Ruiz, never a body beautiful kind of fighter, weighed a fleshy 268 pounds for that bout, which he had taken on a month's notice.

Throughout the build-up to the rematch, Ruiz and his trainer, Manny Robles, have been peppered with questions about how heavy Ruiz would be this time around. Robles wanted him to come in weighing in the 250s since they had a three-month training camp to prepare, but he eventually relented and said as late as a media teleconference with American reporters on Thursday that Ruiz likely would be 268 pounds once again.

Instead Ruiz, the first fighter of Mexican descent to win a heavyweight world title and the underdog once again, was nowhere close at Friday's weigh-in, which took place outdoors at the fight hotel in Riyadh, Saudi Arabia, a little more than 24 hours before he and Joshua meet in an immediate rematch in one of the year's biggest fights.

Granted he was wearing a shirt and sombrero on the scale, but Ruiz (33-1, 22 KOs), 30, of Imperial, California, weighed a staggering 283.7 pounds -- the heaviest of his 10-year career since he was in the mid-290s for his first two professional fights.

In comparison to the generously listed 6-foot-2 Ruiz, the 6-6 Joshua (22-1, 21 KOs) weighed in at a rock-solid 237 pounds. The 30-year-old from England, who is always in fine condition, was trimmed down from the first fight (247.75) but was still ripped.

It is the lightest Joshua has weighed since he was 236.5 for a fight in 2014.

The rematch will take place on Saturday (DAZN, 12 p.m. ET, main event at approximately 3:45 p.m. ET) on the outskirts of Riyadh in Diriyah at a temporary 15,000-seat open-air stadium constructed over the past six weeks specifically for the first heavyweight world title fight to take place in the Middle East.

In other fights on the main card:

• Russian heavyweight Alexander Povetkin (35-2, 24 KOs), a 2004 Olympic gold medallist, weighed 229.3 pounds and 2012 U.S. Olympian Michael Hunter (18-1, 12 KOs), of Las Vegas, weighed 226.8 pounds for their world title elimination bout.

• British heavyweight contender Dillian Whyte (26-1, 18 KOs), allowed to fight despite a recent failed drug test that has not been fully addressed, was a flabby and career-heavy 271 pounds. His opponent, former world title challenger Mariusz Wach (35-5, 19 KOs), of Poland, weighed 270 pounds.

• Fast-rising heavyweight prospect Filip Hrgovic (9-0, 7 KOs), a 2016 Olympic bronze medalist from Croatia, weighed 241 pounds, while former two-time world title challenger Eric Molina (27-5, 19 KOs), of Raymondville, Texas, was 248 pounds.