BOULDER — Kyle Bell was noticeably absent last season, but it takes little to jog the University of Colorado defense's collective memory after its encounter with him in 2005.

"A guy that big — 6-2, 230 coming at you through a hole — it's kind of a rare sight," CU linebacker Jordon Dizon said. "I remember him knocking the snot out of me. It's good for their program to finally have him back."

Added cornerback Terrence Wheatley: "He runs downhill and if you're in his way, you'd better hope you took some aspirin. He's definitely a game-changer."

Bell sat out 2006 with a knee injury, watching the Rams' 14-10 win over the largely punchless Buffaloes. His right knee surgically repaired and apparently fully mended, he returns to the CSU lineup for Saturday's Rocky Mountain Showdown at Invesco Field at Mile High (10 a.m., FSN Rocky Mountain).

CU players and defensive coaches acknowledge the kind of impact Bell can have — if he's allowed to. In 2005, won 31-28 by CU, Bell ran 14 times for 66 yards, with 45 yards after initial contact.

Curiously, CSU seemingly strayed from giving him more carries when the outcome was in doubt. Two games later, in running 33 times for 183 yards against Nevada, he established himself as the Rams' go-to back and one of the most effective ball carriers in the Mountain West Conference.

In the 2005 season's final 10 games, he averaged 26 carries and 109 yards, finishing the season with 1,288 yards and 10 touchdowns. But as Bell begins his comeback, CU doesn't want him punching up rushing numbers anywhere close to those he produced down the stretch in 2005.

"Obviously, they're high on Kyle Bell and want to give him the ball," CU free safety Ryan Walters said. "(But) if we execute and do what we need to do on defense, I don't see how having him in the game is going to change the game."

CU's veteran players differ slightly on what Bell's absence meant for CSU's offense in last season's meeting and what the Rams might attempt offensively Saturday.

With Bell in the lineup, CSU's play-action pass opportunities should increase because CU would be forced to respect Bell's running presence.

Wheatley said CSU missed Bell "quite a bit" last season, while Dizon believes his return won't alter the Rams' fundamental plan.

The biggest thing, Dizon noted, is knowing "they've got someone special out there to run the ball. They're going to try and run it down our throats. We respect them for that. We've just got to take our Tylenol, strap up and expect their best. He's tough to tackle, but we're up to the challenge."

The Buffs run defense was respectable in 2006, yielding 112.4 yards a game (fourth in the Big 12 Conference, 30th in Division I-A). With three of four starting linemen (tackles Brandon Nicolas and George Hypolite, end Maurice Lucas) and two of three starting linebackers (Dizon, Brad Jones) returning, CU's defensive coaches believe there should be marked improvement this season.

"We feel like we gave up unnecessary yardage last season," linebackers coach Brian Cabral said. "We've worked an awful lot against the run. We believe we can be better."

Hypolite agreed, contending the Buffs run defense was inconsistent in 2006.

"We'd hold people to 11 yards rushing, then give up 120 (the next game)," Hypolite said. "This year, I feel like we're going to be more consistent. That's what our defense wants to do — stop the run. Establish the line of scrimmage a yard back, make it easier for the defensive backs to play defensive back."

In determining whether consistency can be achieved, the Buffs won't have the luxury of opening against a warm-up act. There's Bell, healthy, hungry and running behind an offensive line that returns three starters.

"You really can't go into the game saying, 'OK, he's coming off an injury, we're not going to pay attention to him,' " Wheatley said. "You definitely respect all parts of his game."

brooksb@RockyMountainNews.com or 303-954-5466