"I was only 285. Now I'm 295, almost 300 pounds. I've got my strength up a lot; Coach Lou (Hernandez) has helped a lot with that. And just getting and learning the offense. From 1A football, where we have like 6 or 7 plays, to this."
Fortunately, he's a quick learner.
"When I first got here, it was a lot faster. But after I've transitioned pretty good, I think I'm doing okay."
"We've been switching every other day. We're getting the reps to help us get better. That's the only thing we can do, just go out and practice every day. Just mental reps every time. I'm trying out there, I'm giving all I've got."
When the two rookies weren't with the first unit, they backed up three year starter Jeff Allen at weakside tackle. Heitz has no preference, but he's more suited for one than the other right now.
"I'll take both. Either way, that gets me on the field. On the weakside, you're a little more by yourself. You've got to be a little better and tougher. Right now, my and Simon's skill is not there yet. That's why they have us at strong."
What things does he do well as a tackle?
"I don't know. I just know the thing I need to improve on is staying low. That's the big thing right now. I'm doing my best, but I'm not quite there yet."
Heitz is hesitant to brag on himself, but he had no problem describing the Illini defensive player who has given him the most problems in practice.
"It's kind of hard coming down on Craig Wilson with the 330 he's got. The kid's a pretty tough dude, really strong."
He also has no problem discussing the offense. He sees a bright future.
"I think we're coming along really good. We've got the four starting linemen back, so they're gonna be strong. Hopefully me and Simon can step up and hold up the other spot.
"The wide receivers are a little down right now. But they'll step up, I know they will. We've got Nate (Scheelhaase) coming back for his second year. It's gonna be a good year."
Heitz loved the Texas Bowl experience, and he benefitted from the bowl practices.
"It was a blast going down there. Getting to play in the game room and everything else. It was fun just sitting back and learning as much as I can. During bowl practices, I knew next year we wouldn't have Corey and Jeff."
He didn't enjoy being unable to play in the game. Did it make him hungry to play in a bowl down the road?
"Definitely. It's fun going down there, but staying on the sideline all the time for two hours straight is not a lot of fun."
Illinois coach Ron Zook complimented the Animal Science major, although he continues to speak equally both of Heitz and Cvijanovic.
"From the very beginning, him and Simon both are very hard workers, they're very athletic, they're smart. They've got some big shoes to fill, but they'll get better every day. That's what spring practice is for. The more under the gun they are, the better they're gonna be. They're both pretty good sized guys."