COLORADO OFFENSE

To defenses, the Buffaloes are multiple-choice quizzes. They align in three- or four-receiver sets — a fifth if power back Christian Powell or speed backs Phillip Lindsay or Michael Adkins shift from the side of Sefo Liufau to the slot or if they curl in the flats on delayed routes. Most of the time, Liufau is in the shotgun on read options, but he also is comfortable under center as the starting point to three- or five-step drops. Liufau is quick (4.5 seconds over 40 yards) with a big-play arm (22 completions of 25-plus yards in 2014). He has worked on improving his judgment (after throwing late pick-sixes against Washington and Arizona) and endurance (he completed 67.4 percent of his passes on 138.62 efficiency in the first three quarters, but 59.7 percent and 112.29 in the fourth). His favorite receiver is Nelson Spruce, who was targeted 161 times last year. Word is that Spruce, who had 106 catches, has six moves to break free from jamming corners, including the 45-degree release in which he shows a go route, then cuts inside. Shay Fields, who can run 4.4 in the 40, is an option if Spruce is doubled. Fields averaged 15.0 yards on first-down catches last year.

COLORADO DEFENSE

 The Buffaloes’ key signing in February was defensive coordinator Jim Leavitt, who coached the San Francisco 49ers’ linebackers the past four years. A year ago, the Buffaloes relinquished 6.55 yards per play, and amassed only 22 sacks and 15 QB hurries in 12 games. Leavitt, who built South Florida’s program from scratch before being fired as head coach after 13 seasons, is known for his 3-4 schemes. But history does not solve the mystery, and the Buffaloes are expected to go with 3-4, 4-3 and, even, 4-2 looks. Space-eater Justin Solis replaces Josh Tupai at the point. Tupai will be missed as an emotional — and physical — leader. In whatever front, the playmakers are on the edges. Derek McCartney, an end who had a team-high 4.5 sacks in 2014, has a grandfather who really knows about the good old days. Bill McCartney is a College Hall of Fame member and the winningest coach in CU history. Leo Jackson III and Jimmie Gilbert, a 6-5, 230-pound hybrid, will provide heat from the perimeter. In whatever coverage, Chidobe Awuzie stays on the field as a shutdown corner or nickel. Last year, he averaged 7.1 tackles per game and made a team-high 11 third- and fourth-down stops. "Coach Leavitt really brings passion to the game, and it carries over to the defense," Awuzie said.

COLORADO SPECIALISTS

The Buffaloes spent most of this year trying to replace a pair of legs — actually, three legs. Darragh O’Neill could punt with either foot. Alex Kinney gets the shot at punter. Diego Gonzalez will be used on place-kicks and kickoffs. Their best specialist is fullback Jordan Murphy, who had six solo tackles on kick coverages, and 16 blocks that floored a defender or opened a path for a returner. Murphy has overcome an horrific tragedy in 2012 when he was in an Aurora, Colo., movie theater when gunman James Holmes entered and murdered 12 people.

HAWAII OFFENSE

By the end of last year’s first day of training camp, the Warriors lost three receivers (on top of the two who graduated eight months earlier). With defenses pressing their coverages, the wideouts could get could little separation. Leading receiver Quinton Pedroza averaged 3.04 yards after catches; This year, new coordinator Don Bailey upped the tempo, scrapped the playbook and huddle, and spaced the routes. Max Wittek, who redshirted in 2014 after transferring from USC, has a powerful arm that can reach targets 70 yards away, as well as the restraint to make check-down throws to the tight end or slot receivers Dylan Collie and Isaiah Bernard. Wittek’s best throw of training camp was a 1-yard needle to Collie in area as narrow as closing elevator doors. Marcus Kemp, who has gained weight, and Quinton Pedroza, who has dropped 5 pounds, have added branches to their routes. In the past three years, the tight end was a sixth blocker; now Metuisela Unga is a fourth receiver. Running back Diocemy Saint Juste’s availability is iffy, opening the way for Steven Lakalaka to start. Lakalaka’s surgically repaired hamstring has healed. As former Warrior Joey Iosefa’s understudy last year, Lakalaka averaged 3.04 yards after he was initially hit or eluded a defender. He averaged 0.52 broken tackles per rush.

HAWAII DEFENSE

Defensive coordinator Tom Mason is not concerned about the perceived lack of depth on the defensive line. Several times as SMU’s play-caller, he attacked with two down linemen. Against Texas Tech, SMU rushed one lineman. Mason employs a movement-type approach in which linemen are continually shifting, stunting and looping to create one-on-one matchups. What makes the system effective is tall linebackers on the edge and nimble inside linebackers. There are 10 linebackers who will rotate in the base scheme’s four spots. Jerrol Garcia-Williams, who missed most of the 2014 season with a knee injury, has moved from the outside. "He’s your prototype NFL inside linebacker," Mason said. The Warriors have added fire-zone schemes that will require the corners to play tight coverages and everybody else to blitz. Jalen Rogers, who played four DB positions a year ago, has emerged as the physical corner. Mason’s office is filled with videos from teams using 3-4 defenses. He also studied under Dick LeBeau, considered the Yoda of the 3-4. "I like to be a little creative, too," Mason said.

HAWAII SPECIAL TEAMS

You can set a clock to short-snapper Brodie Nakama — well, if you want to be 15 minutes early. There was panic when Nakama was not early for a meeting this week. As it turned out, a door-lock malfunctioned, trapping him in the room. On the field, Nakama is like clockwork. He enters the season with 102 snaps without an error. There is competition, with Noah Borden, who returned from a church mission this spring, a candidate at both snapping positions. There also is competition at kicker (Rigo Sanchez and Mauro Bondi) and punter (Alex Trifonovitch and Sanchez). Sanchez, who will punt against Colorado, wowed teammates when he easily booted a 53-yard kick — with 10 yards to spare — during a recent practice.

ENLARGE CHART