"It felt awesome," said Kelce, who previously was limited through most of the spring. "I haven't played football really against a defense in eight months. Not only that, but it felt good to have all the guys there that are projected to be there."
All four veteran linemen are returning from injuries and surgeries. Kelce tore the anterior cruciate and medial cruciate ligaments in his right knee in the second game of last season. Peters ruptured the Achilles tendon in his right leg last March, and again a month later.
Herremans broke his right foot in November. Mathis, who was the only lineman to start all 16 games in 2012, underwent surgery on his left ankle last month and was expected to miss all of the spring.
"It got to the point where I was just pushing everything full speed," the left guard said. "And I was like, 'Look, there's no point in me waiting anymore. I want to practice. Let's go.' "
All eyes, though, continue to be on Peters, the all-pro left tackle. He was a full participant Tuesday after missing the final two weeks of voluntary organized team activities attending to a personal issue.
"It's personal. If I told you, it wouldn't be personal," Peters told reporters. "I spoke to Coach, and he knew where I was at . . . and when I would get back."
In April, the 340-pound Peters said he hoped to get down to a playing weight of 325 so that, among other reasons, he would be fit enough to play in Kelly's up-tempo offense. Shedding pounds also should aid the 31-year-old tackle's return from the Achilles injury.
"He can move," Mathis said. "He didn't lose a step at all."
Herremans has been healthy through all of camp. After two seasons at right tackle, he is being asked to move back to guard. He is moving inside to make way for Johnson, selected fourth overall in the draft in April.
"I think he's keeping up," Mathis said. "He's doing a really good job. He's a smart kid . . . and we still have plenty of time before the first game."
There's still a lot to learn. Kelly's spread offense cannot thrive without a cohesive line. It was often his secret weapon at Oregon. Communication is key.
"You're getting the call from the sideline a lot of the times, so you've got to be able to echo that," Mathis explained. "Say somebody didn't see the call. That could happen. . . . There's a lot of talking. Talking is good. Any offensive line should do that."
This offensive line, despite the injuries and Johnson's relative inexperience at tackle, has the potential to be a strength for the team.
"Personnel-wise, I think we have a lot of very good offensive linemen," Kelce said. "Now, as long as we can jell and work everything together through training camp, I think we have a chance to be a very good offensive line."
Contact Jeff McLane at firstname.lastname@example.org. Follow on Twitter @Jeff_McLane.