In the three weeks since the Colorado Buffaloes' football season ended, something happened that defensive coordinator Greg Brown wasn't sure was possible.
His job became even more difficult.
Four new head coaches have been hired in the Pac-12 and at least three of them will make an already punishing offensive league even more grueling for the conference's defensive coordinators.
Brown will face them all in 2012.
The Buffs are scheduled to travel to play Rich Rodriguez at Arizona and Mike Leach at Washington State. UCLA coach Jim Mora and Arizona State coach Todd Graham will bring their teams to Boulder.
"It's huge," Brown said of the challenge he and other defensive coordinators in the Pac-12 will face in 2012 and beyond. "You're getting some established offensive minds in there that have been there and done that and had a lot of success in their respective programs. It's just another great challenge for Colorado to face next year."
The Pac-12 wasn't lacking for offensive ingenuity.
Eight Pac-12 offenses averaged 30 points a game in 2011 and five of them averaged at least 450 yards of total offense each week.
Oregon is widely considered one of the most innovative schemes in the nation. USC and Stanford are just as talented but play a different style.
There are a handful of other teams right behind those elite
Offense was considered the strength of each of the programs that hired a new coach and those coaches should only build on that strength.
Arizona State became the final Pac-12 school to fill its coaching vacancy Wednesday when it hired Pitt coach Todd Graham, who had only spent one year with the Panthers after four seasons at Tulsa.
His offenses at Tulsa twice led the nation in total offense (2007 and 2008) and finished fifth in the nation in 2010.
Mike Leach led Texas Tech to 10 consecutive bowl games during his tenure in Lubbock, and in six of those 10 seasons, the Red Raiders led the nation in passing. They led the nation in total offense three times.
Brown called Leach "an outstanding teacher and molder of quarterbacks."
Prior to three difficult seasons as head coach at Michigan, Rodriguez led West Virginia to four Big East championships between 2001 and 2007 with a dynamic spread offense.
Even at Michigan, his offense proved difficult to stop and the quarterback he recruited to run it. Denard Robinson, has been among the most electrifying players in college football the past two seasons.
UCLA hired Noel Mazzone, who was an assistant coach at Boulder High School in 1981, as offensive coordinator. Mazzone spent this season in the same job at ASU where the Sun Devils finished 26th in the nation in total offense.
Brown, who coached one year in the Pac-10 in 2010 before returning to CU to help the Buffs make their Pac-12 debut, predicted CU would struggle in its first season to keep up in its new league.
The Buffs' speed shortcoming is at the top of the list of issues the coaching staff is trying to address in recruiting.
"You need a great deal of speed," Brown said. "You have to be very careful putting guys out there that can't run. These upper-echelon teams, they've got guys who can go by you quickly. They've got not only speed, but they are big, imposing people. It was a great learning lesson the first year. Now let's see if we can take the lessons that we learned this first year and take a step forward."
While the challenge to stop opponents has grown, it's difficult to imagine the Buffs doing worse.
CU finished last in the league in scoring defense, allowing 36.5 points per game.
The Buffs were 11th in total defense, surrendering 439 yards per game, and 10th in rushing defense, giving up 184 yards a game.
The Buffs gave up a conference-high 34 touchdown passes and made just seven interceptions. Only Stanford intercepted fewer passes.
Colorado gave up 307 first downs. UCLA was the only other team in the conference to allow more than 280.
CU opponents converted on third downs 47 percent of the time. Only three Pac-12 defenses had a more difficult time getting off the field on third downs than the Buffs.
And finally the Buffs were last in the league in red zone defenses, allowing teams to score 92 percent of the time. The CU defense didn't come up with a turnover in the red zone all season.
A slew of injuries ravaged a defense already lacking depth this fall.
CU figures to be better equipped to survive next season with a lot of young talent to fill gaps on the depth chart and a less daunting nonconference schedule.
"At least we had some young guys get some experience," Brown said. "Everybody got their feet wet in the Pac-12 and know what to expect. It's just challenge upon challenge week after week. At least our eyes have been opened to the threat and challenges of playing against these offenses in the Pac-12."