"It felt good," he said. "I remember my first hit today. I got hit in the head. My right side went blank. I couldn't see out of my right eye. It's football time. It brought back that football feeling and I was ready to go.
"It's all good. I was going to block somebody. It wasn't a catch, just a block. It felt good. It was all fun. You just hope you have a couple of seconds to get your vision back for the next play. I had my left eye, so I was all right. I got it all back."
Overall, it was a great day in full pads.
"It came out pretty good," said Williams, who's trying to impress coaches with his pass blocking after mainly turning heads with his pass catching in an impressive fall campaign. "You always try to start with yourself first. I tried to come out and focus on the physical part.
"I changed the mentality from last year that catching balls were all the good things in the world. I understand blocking is just as much an important part of the game and that's my focus for this spring. I want to be more physical and that's an overall goal for the whole team. We are starting off pretty good with that."
Petrino said on Monday in his pre-spring media briefing that Williams had been challenged to block better and improve his technique. After Friday's practice Petrino said he thinks Williams has improved, but wanted to see video to know specifics.
"I really don't see the tight ends' technique until tape study," Petrino said. "My eyes are somewhere else during practice. I think D. J. is doing well, but we'll look at tape. He's worked hard to become more physical."
Williams understood the tape study answer. He's the same way.
"The tape helps a lot," he said. "When you are out here on the field and you hear the coaches yell at you, there is a thought that you did everything right. You go back and watch the film and you see what they are trying to coach and it helps a lot. You see the film on how important the technique is. Just six inches on a step can make a huge difference in getting an edge over your man."
The added weight -- around 15 pounds up from last fall -- has turned out to be a big help.
"I'm not as round as I thought I'd be," he said, noting his speed is still good. "The strength program did a great job of that. Feel pretty good, just as fast."
Williams said he's got plenty of solid company at tight end with Ben Cleveland and Chris Gragg both having good starts to spring drills.
"We've got a lot of good tight ends," he said. "Gragg is very impressive. Gragg has improved so much from last year. It doesn't seem like he's gotten bigger, but he's added 20 pounds. He has a big frame to hold it and ran a 4.4 40. He's going to be a huge addition and I can't wait to see him play.
"The entire corps of tight ends is doing well. Ben Cleveland, Joseph Henry and Chris Gragg are all coming along. We are helping each other and competition is great."
Williams said some of Ryan Mallett's throws are so hard they twist his gloves on his hands. Petrino said Mallett sometimes unloads "full hummers" when that's not needed. Williams said he's gotten a few full hummers.
"I've gotten plenty," he said. "There are times that my gloves get turned around and I have to turn them back around. So he's bringing it. You have to focus extra hard and catch those things."