There was plenty of speculation Ruiz had dropped a stack of weight since the pair last stepped into the ring but the 30-year-old surprised everyone by weighing in at a whopping 128.4kg — 7kg heavier than he was in June.
Russian giant Nikolai Valuev — who stands 213cm tall — is the only fighter to weigh in heavier for a fight and it was the heaviest Ruiz has been in his decade-long professional career.
Ruiz's trainer Manny Robles had said Ruiz was too heavy fighting at 121.5kg in New York for the first fight with Joshua and was only that weight because he fought at late notice. That Ruiz has come in even heavier five months later was surprising.
Promoter Eddie Hearn doesn't think Ruiz's weight gain will have an impact on his performance but took a cheeky jab at the Mexican, saying: "I was actually expecting him to come in lighter. Ruiz said to me, 'It's because I've just had lunch' and I was like, 'What did you eat, your trainer?'"
Meanwhile, Rafael suggested Ruiz hasn't trained properly.
But the fighter isn't concerned about his physical conditioning, despite what the scales said.
"They made us wait until 4:30, almost 5pm here," Ruiz complained. "I already had ate breakfast, lunch and dinner. I had on a sombrero and all my clothes.
"A lot of people are saying that I came overweight or this and that. We had to wait so long. I probably put on like 10 pounds (4.5kg) just eating and drinking normally today.
"We were lighter during camp, but then I thought being the same weight or heavier would be an advantage. We did so many 12 rounds of sparring, so the conditioning is still there."
Joshua has shed muscle mass in order to improve his mobility around the ring.
"Before I was trying to bench press a house. I used my body to get where I needed but then I started realising the sweet science of the sport," Joshua said.
"I am punching like a horse kicking backwards right now."
The stakes could not be higher for Joshua, who would face a long road back to the pinnacle of the heavyweight division if he loses Sunday's much-hyped fight.
