It had nothing to do with temperatures in the mid-90s and humidity so thick you could swim in it. It had nothing to do with being beaten on a particular play during minicamp.
It had everything to do with having to wear boxing mitts the size of Mickey Mouse hands.
"Yeah. I am frustrated," Norman said after Tuesday's practice. "Can't you tell?"
The mitts are the latest ploy to get cornerbacks such as Norman and Antoine Cason to use their feet more than their hands. With the NFL emphasizing defensive backs keeping their hands off of wide receivers, the frustrating experience could be a good thing once the season begins.
But it is frustrating.
"Very frustrating," Norman said. "I don't care for them. It feels like [Mickey Mouse hands], especially when you're running. You can't really drive. I don't know. It's more so a technique thing than anything, just moving your feet.
"You have those big mitts on your hands, trying to run and defend these fast guys out there, it's hard to do. I guess it makes us that much better."
That is the point. Norman in particular has shown tremendous ability in practice and preseason games the past two years, but in games he has struggled. That has kept him off the field. For much of last season, it kept him on the inactive list.
The gloves simply are a tool to help him maximize his abilities as a big (6-foot, 200 pounds) cornerback that could help take the league's No. 2 defense to another level.
The same for Cason (6-1, 195).
"He is doing it because he’s used to grabbing and holding," wide receiver Jason Avant said of Cason. "He can’t grab and hold. It is good practice for him. A lot of times you reach out as a corner you forget to move your feet and you reach out and grab. So he is trying to work on his craft."
Refinement is what minicamp is all about for many. If that means using tools that make you look like a Disney character, so be it.
"They’re using their arms and hands the right way and they’re developing some good habits, and we’re trying to break some old and bad habits,” coach Ron Rivera said.
Norman might not like it, but he understands.
He just hopes they don't take it too far, like making them eat with the mitts.
"Nah, man," he said. "Don't even suggest that."