STANFORD, Calif. -- David Shaw's program closed the 2014 season on what was possibly its best three-game offensive stretch since Andrew Luck roamed campus, so optimism has flowed freely the past eight months.

"Our goal is to pick up the script where we left off last year," quarterback Kevin Hogan said in March.

But when Northwestern muzzled Stanford 16-6 this past Saturday, hope for continued success ran face first into a brick wall.

It was an offensive fiasco; a dreaded reversion to earlier struggles that had led to critical losses.

The Cardinal averaged 3.9 yards per play against the Wildcats, better than only two games since 2008: last season's 17-14 loss at Notre Dame (3.0 yards per play in driving rain) and a 17-13 setback at Washington in 2012 (3.7 yards per play). Hogan managed only 4.4 yards per pass attempt against Northwestern, Stanford's lowest average since the pre-Luck era.

The Cardinal's only scoring came via a pair of field goals, and they still seemed to be reeling on Tuesday.

"We could have done so many things differently," Hogan lamented. "So many things better."

Stanford had hoped that offensive regrets had passed with last season's finish, in which the team surged by scoring 38 points per game throughout commanding wins against Cal, UCLA, and Maryland. Saturday's data point, however, re-opened scars of frustration.

"Offensively and defensively, we did just about everything we could to help yourself lose the game," Shaw said.

The offense was the bigger culprit. The Cardinal suffered death by a dozen cuts on that side of the ball: Wobbly passes, poor routes, bad drops, inconsistent blocking, a pair of substitution penalties, and a punt from Northwestern's 37-yard line while trailing in the second half all minimized Stanford's scoring chances.

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While Shaw maintains that wholesale changes aren't necessary, the sheer diversity of his team's offensive problems remains startling. And unlike Stanford's relatively inexperienced defense (which, by holding Northwestern to 16 points and 4.2 yards per play, ultimately gave the Cardinal a reasonable chance to win), the squad's offense is laden with veterans -- Hogan is a fifth-year senior -- so its abysmal numbers were particularly disheartening.

"We need to be efficient in our passing game and we were not," Shaw said. "You feel stagnant when you don't complete the standard six- or seven-yard passes [on first and second downs] to get to third and medium."

The Cardinal are banking on a domino effect of positive developments to take hold, starting in this Saturday's home opener against Central Florida. To begin, an offensive line comprised of formerly touted recruits -- most of whom are upperclassmen now -- must improve significantly. The hope is that progress up front can pave the way for offensive aggressiveness that shepherds Hogan back into his comfort zone.

"I like getting into a rhythm, I think anyone will tell you that," he said. "Anything that gets our offense into a rhythm, I'm OK with."

It's no secret that Hogan's athleticism is the attribute that most makes him tick, and in the past, he hasn't been shy about lobbying for plays that help establish his presence in the running game. Perhaps it's no coincidence Hogan averaged seven carries and nearly 50 rushing yards per game during 2014's hot finish. That total plunged to -9 yards on the ground at Northwestern, a dive that mirrored the crashing efficiency of Stanford's passing attack.

The Cardinal must flatten out this offensive roller coaster if they intend to stay afloat in 2015.

For the past three years, Stanford has featured one of the nation's best defenses, and they were often able to overcome their offensive struggles as a result. But the once-dominant unit lost eight starters in the offseason, and it suffered another blow when lineman Harrison Phillips -- one of its promising young cogs -- tore his ACL at Northwestern.

"It's sad," Shaw said. "He was just starting to really show what he can do."

The defense remains effective, but it appears its airtight security blanket of years past is gone. Northwestern slapped cold reality into the Cardinal: Shaw must lead consistent offensive success. The mercurial ways of the past three years will no longer be good enough for a winning record. If 2014's five losses didn't deliver that message effectively enough, then Saturday's rude awakening barks the warning even more loudly.

With UCF waiting and USC looming behind the Black Knights on the schedule, it's time to see if Stanford's offense can answer the bell.