Colorado has the task of trying to replace all three starting defensive linemen this next season.
Assistant coach Jim Jeffcoat views it as an exciting challenge, however, as the Buffaloes prepare to open spring football next week.
"I'm always excited," the Buffs' defensive line coach said of working with inexperienced players this spring. "It brings me energy when I have the young guys and have the opportunity to work with them, because I like to teach and I like having those young guys and bring them to the next level."
Last season, when the Buffs went 10-4 and won the Pac-12 South title, their defense was anchored up front by a trio of talented seniors — Jordan Carrell, Samson Kafovalu and Josh Tupou.
Those three are gone, meaning CU will spend the offseason trying to fill those holes.
"I haven't been on the field with them (this offseason) and we understand it's a process," Jeffcoat said.
CU won't be devoid of experience this spring.
Seniors Timothy Coleman and Leo Jackson III were second teamers up front, with Jackson logging 254 plays and Coleman 174. Jackson, in fact, started 10 games in 2015, and Coleman has 30 career games under his belt.
Junior Jase Franke spent this past season as the backup to Tupou at nose tackle, making 11 tackles in only 76 snaps.
Redshirt sophomores Brett Tonz, Lyle Tuiloma and Frank Umu will enter their third year in the program, although they've played sparingly, and juniors Eddy Lopez and Michael Mathewes are back, as well.
Strength and conditioning coach Drew Wilson said the returning group up front seems to be dialed in this offseason, knowing the opportunity in front of them.
"They all know we need to get stronger, they all know we need to get bigger," Wilson sad. "They're all reminded every day. You have to mentally accept the job we're asking you to do.
"I think we have the guys that can do it."
Giving the Buffs a boost on the defensive line this spring will be junior college transfers Javier Edwards and Chris Mulumba.
The 6-foot-4, 280-pound Mulumba figures to push for playing time as an end, while Edwards could be in line to fill Tupou's shoes at nose tackle.
Edwards is listed at 6-foot-3, 350 pounds, but Wilson said he didn't want to disclose Edwards' current weight.
"He understands he needs to get his weight down," Wilson said. "He's going to be a strong kid. He's built the right way. He's built like Josh, a thick compact nose tackle that you need in a 3-4 scheme to man that middle. Realistically ... he's probably going to play around 350-355 this year."
Wilson said Edwards has been working hard since arriving in January and puts in extra work on his own to get in shape. Wilson added that considering how well Edwards moves for his size, "he's a natural athlete."
It appears to be a talented and determined group, and Jeffcoat is eager to see how they respond to the opportunity this spring.
"We'll see where they're at in the spring," he said. "We'll see what we have to work on and what we have to get better at and what we're good at.
"They have the athletic ability to play well. We're going to have to work on some things; that's just every year, you have to work on and correct some things."
Redshirt freshman Terriek Roberts and incoming freshmen Jacob Callier, Sebastian Olver and Dante Sparaco could also give the Buffs a lift at end. Sparaco arrived in January and will go through spring ball.
Former Rock Canyon High School quarterback Josh Goldin announced on Twitter on Tuesday that he plans to join CU as a preferred walk-on. A 2016 graduate of Rock Canyon, he threw for 1,577 yards, 14 touchdowns and four interceptions as a senior in 2015.