Marcos Maidana is confident of causing an upset in his highly anticipated rematch against Floyd Mayweather Jr on Saturday.
The Argentine, 31, went close to upsetting Mayweather in May, losing by a majority decision in Las Vegas.
Mayweather (46-0) gave Maidana a rematch, putting his undefeated record and WBA and WBC welterweight belts on the line.
After a weigh-in at the MGM Grand, Maidana (35-4) told reporters the result would be different this time.
"The first fight was very close," he said.
"I made a couple of errors and I will rectify those and we will see a different result.
"My punches weren't that accurate, that is why I did not win the fight but this time they are going to be."
As the weigh-in ended without incident, Mayweather is wary of Maidana.
The 37-year-old American, who plans to retire in 2015, said he would perform better.
"It was a good competitive fight. I won, you live, you learn what else can I say," he said.
"The only thing you want to do is make things better always.
"I can make adjustments, that's happened before in my career. No-one is perfect, I was trying to be a perfectionist but no one is perfect."