Clemson coach Tommy Bowden reported prior to the end of Monday morning's practice that Jackson will miss at least half the season thanks to a knee injury he suffered early in Saturday's scrimmage.
"I'm stepping in now and I'm going to try and have some leadership out there," Cumbie said. "There is one thing I have always done, I work hard and everyone knows it. I try to push everyone. We all work as a team out there."
Jackson is scheduled to have surgery Tuesday on his right knee to repair a torn quad tendon. Jackson was unavailable for comment.
"You lose a lot, not only just play on the field, just his energy and his leadership and what he brings to the field every day in practice and what he teach those guys. We are going to miss him a lot," Clemson defensive line coach Chris Rumph said.
With Jackson out, Cumbie is currently listed as the starting defensive tackle with Jenkins slotted in as the second-team tackle. Jock McKissic, who moved back over to the defensive front at the start of camp, is third.
"Jock is just coming back and I don't think he is ready right now to get back in the flow of things, at least right now," Rumph said. "Right now, I feel comfortable with Jamie and Jarvis and what they have done this far in camp so we are just going to go forward with those guys."
Cumbie did a lot of work with the first-team Monday morning, but the coaches are concerned that his 6-foot-7, 270-pound frame might cause him to be at a disadvantage, especially when it comes to stopping the run.
"That's a big concern with Jamie and I know he is really working hard at it," defensive coordinator Vic Koenning said. "Jamie has become a guys that is hard to single block and a lot of times a three-technique gets singled blocked in pass situations and I think Jamie is going to be an effective player, but what we have to work on is the run blocking side of it and I know that's a big emphasis."
And that's where Jenkins and his 6-foot-4, 300-pound frame comes in. Jenkins has had one of the best camps among all the defensive linemen and had the coaches feeling he not only could be a starter now for the Aug. 30 Alabama game, but they felt he might have had that shot even if Jackson had not got hurt.
"I was talking to Coach Rumph about Jarvis being a first-team guy before Rashaad got hurt," Koenning said. "We're thinking he is doing that well."
Koenning has admired just about everything Jenkins has done since mat drills last winter. In fact, Jenkins reported to camp nearly 25 pounds lighter than he was at this time last year.
"I think that has a lot to do with it," Koenning said. "The more he hangs around Dorell Scott and mimics his work ethic. You know they talk about leadership, if they do what he is doing then they will all be headed in the right direction."
Koenning said Jenkins "work ethic and his attention to detail have been good and obviously there are a few little things that he can always get better at. He gets cutoff occasionally because he is coming out of his stance too fast, if that's such a thing."
Last year, Jenkins totaled eight tackles in 100 snaps, including a sack of Florida State quarterback Drew Weatherford on just his second play of his career. He missed the South Carolina and Auburn games last year after injuring his right wrist, which he had surgery on following the South Carolina game.
"I got kind of used to the game speed and I learned the plays," the sophomore said. "Last year with me playing, really helped me learn the plays, the game speed and how I have to react when stuff is on the line. It was a real good experience for me."
Jenkins says being in this position is why he dedicated himself to dropping the weight.
"This is what every player works for," he said. "You never know when your time is going to come up. As hard as I worked this summer, I just have to produce for my team. My team captain is down so this is something I have to do.
"I hope Rashaad gets back as soon as he can, but right now, I'm going to help out the team as much as I can."
Jenkins, Cumbie in Spotlight
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