Derrick James, the head trainer of IBF welterweight champion Errol Spence, believes size will not be the deciding factor on March 16th - when his fighter defends the title against four division world champion Mikey Garcia.
The contest takes place at AT&T Stadium in Texas, and the bout headlines a Fox Sports Pay-Per-View event.
Garcia, who holds the WBC lightweight world title, is moving up by two weight divisions to take the fight.
Garcia is a massive underdog, despite his pound for pound status with most respected observers.
Most of the focus has been on the size disparity between the two boxers.
But James argues that Spence is just a better skilled fighter and that is the main factor that will bank him the victory.
He believes Spence is going to put on a boxing clinic when he gets his hands on Garcia.
Garcia has captured world titles at featherweight, super featherweight, lightweight, and junior welterweight. He wants to gain a fifth world title.
"This fight is all about the skillset, not the size. Size will come into play a little bit, but we're going to show the skillset that we have to beat this guy. That's what Errol is going to show," James said.
"Mikey Garcia has a good technical style. But there's always a method to take down a great fighter. I think that a day like today will inspire us even more to work even harder. We can see him right in front of us. Its real and we can't wait.
"When I first saw Errol we were actually sparring each other. We started working together and I got to see him walk through guy after guy. We knew he was a great athlete, but it took time to build to where I started to realize he was something special."