But that's all behind him now. There's more than enough of his final season of college football remaining to reclaim and make it worthwhile.
After a three-game absence, Colorado's senior middle linebacker is set to return Thursday night against Arizona State at Folsom Field (7 p.m., ESPN). That leaves seven games - seven difficult games - in his CU career, and Rippy intends to make the most of them.
"I'm excited . . . I feel like it's been a very, very long time," he said before Monday's practice. "I'm feeling 100 percent. Injuries like this take time, but now I can't tell there was anything wrong with my right knee - the one I had repaired. That's a good thing, and I'm feeling great.
"There are seven games left and it's my senior year. You don't expect things to happen, especially your senior year. It happened. I think it might have been a good sign to get me to quit worrying about my other (right) knee. I'm just ready; I feel like myself."
The injury to Rippy's right knee required surgery and forced him to sit out the last half of the 2011 season. He tweaked his left knee in game two this season and spent the next three weeks as a spectator. Touted as one of the Buffs' top two or three returning defensive players, his leadership as well as his on-field ability have been missed.
Veteran linebackers coach Brian Cabral will be happier than most to welcome Rippy back, but he still plans to be cautious about how he uses him. "I'll break him in (slowly)," Cabral said. "I'm not going to throw him to the wolves . . . but, yeah, we can sure use his leadership."
After a bye week that saw the team get a couple of days (Friday/Saturday) off, Rippy and the Buffs plunge into their final seven games with a 1-4 overall record. Their lone win came at Washington State two games ago and leaves them at 1-1 in the Pac-12 Conference's South Division. ASU leads the South at 2-0 (4-1 overall) and also appears to be prospering statistically under first-year coach Todd Graham.
Rippy called the bye week beneficial from the standpoints of recuperation and refocusing. "We'll get some guys back," he said, "and mentally, I felt like we needed a break, some time off. It was rocky start to the season. Guys needed to get refocused.
"These past three or four weeks helped me get refocused and get back on track. Coming off an injury, you're worried about it. You want to go out and play, but at the same time, sometimes physically you feel all right, sometimes you don't. I feel like I'm back now."
From his vantage point on the sidelines the last three weeks, Rippy said he couldn't question the Buffs' "effort, our toughness." But he added that he saw a leadership void: "The same guys can't lead all the time. Other guys have to step up. Once we get that, I think we'll be fine. We have a lot of young guys playing; with that being said, they make a mistake and sometimes they might get down on themselves. Other guys have to pull them out of that."
In Rippy's place in the middle for the past three games, Cabral has plugged in sophomore Brady Daigh. "He's done very well," Cabral said. "That position for the future looks very bright."
Daigh's strongest suit might be as a run-stopper against two-back offenses - an alignment that's not so prevalent in the spread-it-out, throw-it-around Pac-12. But, Cabral adds, "I've been very, very pleased with how he's responded to spread teams."
That's what Rippy, Daigh and the Buffs will encounter on Thursday night. Under Graham, the Sun Devils have been among the conference's most prolific offensive teams. Averaging 38.4 points a game, they're second (behind Oregon) in scoring and fifth in total offense (456.2 yards). Quarterback Taylor Kelly, ASU's heir to Broncos backup Brock Osweiler, leads the Pac-12 in passing efficiency, having completed 92 of 136 for 1,292 yards, with nine touchdown passes against only two interceptions.
CU defensive coordinator Greg Brown said Graham's offense features "an extreme amount of misdirection" with Kelly running a variety of option plays. "And they've got guys. As good as people as they had last year, they're every bit as good if not better."
Plus, the Sun Devils might be more disciplined under Graham than in their final season under Dennis Erickson. Said Brown: "There certainly seems to be a disciplined approach and he's (Graham) gotten it out of them. There doesn't seem to be a lot of freelancing. People are where they're supposed to be and doing what they're supposed to do. They're executing. They're really good."
Defensively, ASU also is among the Pac-12's leaders, ranking first in scoring defense (13.6 points), total defense (276.2 yards), pass defense (137 yards) and pass defense efficiency (90.2 rating, four TD passes).
"They're executing at a very high level," Brown said. "They're a no-huddle team and like most people (in the Pac-12), they're going at a break-neck speed, coming at you 100 miles an hour . . . you look at their statistics, where they are, and it's justified. They're an excellent team."
ASU was among others receiving votes in this week's AP national rankings, but CU's next three opponents - at Southern California, Oct. 20, 4 p.m. MDT; at Oregon, Oct. 27; Stanford, Nov. 3 - all are positioned in the Top 25. The Trojans are No. 11, Oregon is No. 2, Stanford is No. 17.
Rippy said that stretch, followed by Arizona, Washington and Utah, is "what we're here for. Those guys put on their pads the same way we do . . . I look at it as a challenge. I didn't get to play (last season) against some of these teams we're playing. I feel like if our mentality and effort matches theirs we'll be fine. We've just got to have that 'punch first' mentality."
Rippy's knee injury kept him out of last season's "blackout" game against USC, yet another reason he's anticipating Thursday's visit by ASU. The "blackout" concept - CU fans decked out in black - "is good," he said, "but at the same time, that's just for the fans. We play for Colorado and the people that played behind us. That's the main thing. I think a lot of people forget that because your name is on the back of your jersey. The first thing I play for is the guys around me and the guys who played before me here. Once you figure out the tradition here it means a lot."
BUFF BITS: The Buffs' Sunday and Monday practices, said coach Jon Embree, were physical and productive. He characterized Monday's work as being better than Sunday's and said Tuesday "has to be even better . . . then we go play." . . . . With an open date last Saturday and this week's game on Thursday, the Buffs have the equivalent of two bye weeks - or at least two Saturdays open. That's fine with Embree, who says he isn't opposed to playing on "any day of the week - as long as it's at home." . . . . The Buffs will be "head-to-toe in black" against the Sun Devils, said Embree, including wearing black helmets . . . . Sophomore Connor Wood, who apparently is over a sternum ailment, will enter Thursday night's game backing up starting quarterback Jordan Webb.