Four months ago, Floyd Mayweather was expected to easily handle Marcos Maidana and move on to a different opponent in September. After the underdog gave Mayweather one of the toughest fights of his career, the two are set to square off again in a rematch this Saturday.

Mayweather vs. Maidana II is set to take place at the MGM Grand Garden Arena, where the two fighters went head-to-head on May 3. Mayweather improved his career record to 46-0, picking up the majority decision. While Mayweather entered the bout as a heavy favorite, he didn’t have an easy time against the challenger, who showed few signs of intimidation.

Maidana got out of the gate strong, winning at least two of the first five rounds on all three judges’ scorecards. He was much less accurate than Mayweather, but only landed nine fewer total punches, according to CompuBox. Mayweather settled in during the second half of the fight, but that doesn’t necessarily mean Saturday’s bout will be any less difficult.

“I think it’s a canard to say that once Mayweather figured him out he dominated the second part of the fight,” Showtime broadcaster Al Bernstein, who was on the call for the fight in May, told International Business Times. “He won most of the second part of the fight, but I don’t believe he dominated. And so there were a couple of rounds that I thought Maidana won… and so it’s not as if all of a sudden now Mayweather has him completely figured out and now he’s going to walk over him for 12 rounds.”

Prior to his fight with Mayweather, Maidana had won four bouts in a row, including a unanimous decision against Adrien Broner in December. His unorthodox style gave Mayweather trouble, but he was unable to score the victory. In their rematch, Maidana says he’ll try to win via knockout.

While Maidana made a believer out of some in May, he did little to convince Mayweather that he has a legitimate chance to become the first blemish on the undefeated boxer’s perfect record. Soon after the fight, Mayweather disregarded the idea that Maidana ever had a real chance of winning.

"Miguel Cotto was a tougher fighter and he hit harder," Mayweather said. "Canelo hit harder than him. I don't take nothing away from him, he's tough and he's very, very rugged. Now, I could make this fight absolutely easy but it would be boring, and I didn't want to do that for the fans. These fans are paying serious money to come out here and support boxing."

Maidana’s first effort has made him a more formidable opponent in the eyes of the oddsmakers, but a loss for Mayweather would still be a considerable upset. The betting odds at Bovada.lv have Mayweather listed as a -800 favorite, with the odds of Maidana winning coming in at +500.

Prediction: Mayweather’s assessment that the first fight was only close because he allowed it to be feels like a bit of a stretch. Maidana had success using his different style and forcing Mayweather to the ropes. In the rematch, though, Mayweather should make a few adjustment that help him win more decisively. He did the same in his only other rematch against Jose Luis Castillo, and the greatest boxer of his generation should see a similar result on Saturday,

Mayweather by unanimous decision