ESPN's Mike Greenberg disagrees with Danny Kanell's tweet saying Stanford should have made it into the top four of the College Football Playoff. Kanell goes on to explain why he believes the playoff should be expanded. (1:45)

When the calendar turned to November this season, the "defense wins championships" cliche seemed to be flying out the window at Stanford. The Cardinal were profusely leaking oil on that side of the ball. Oregon and Notre Dame scorched the earth against Stanford, averaging over 10 yards per play for most of both games.

By that metric, those were the two worst Cardinal defensive performances of the Jim Harbaugh-David Shaw era. It appeared that Shaw's offense would have to carry the entire load for Stanford to secure a Pac-12 championship.

But a moment of truth came last Saturday in the Pac-12 Championship Game. When the Cardinal attack sputtered early in the third quarter, it became clear that they wouldn't be able to finish the job alone. USC’s offensive line found its road-grading rhythm. And although Christian McCaffrey’s 67-yard catch-and-run pushed Stanford back on top, the Trojans began another methodical march to retake the lead.

USC ripped off big chunks of yardage with the power run. The Trojans swallowed the Cardinal's pass rush on third downs, setting the table for Cody Kessler’s arm to move the chains. So the cliche returned, kicking and screaming: No matter how good Stanford's offense had been in 2015 -- they led the Pac-12 by scoring 41 points per game -- the other side of the ball would have to deliver, or a championship wouldn't come.

"We knew our defense would have to make a play," Shaw said.

Cardinal defensive end Solomon Thomas (90) returned a fumble for a touchdown in the Pac-12 championship game. Cary Edmondson/USA TODAY Sports

Did it ever.

Linebacker Blake Martinez surged past the center on a blitz, crunching Kessler's back just before the quarterback released the ball.

"The moment hit us when they started making some plays," Martinez said. "Once they started hitting us in the mouth, we pulled it all together on the sideline and said, 'Hey, we need to bring it back.'"

Stanford took those last words words literally: When the ball popped loose from Kessler's arm, Solomon Thomas scooped it up and did indeed bring it back -- all the way to the end zone, with grace more fitting of a wide receiver than a defensive lineman.

And that was the play that put the Pac-12 championship under Stanford control. It also simultaneously defined the 2015 Cardinal defense.

After losing nine starters from last season, this was not the same dominant unit that had been the class of the Pac-12 for three years running. In fact, Stanford's crew took some massive lumps in 2015, especially when Ronnie Harris’ absence meant that the secondary had no starting experience and injuries forced three defensive linemen to play over 550 snaps each.

But it ultimately proved to be a defense that got the job done at critical junctures, even when reeling down the stretch: They held Notre Dame to one touchdown in five red-zone trips -- the difference in that win -- and they reversed the dominance of USC's offensive line just in time to deliver a game-changing play and give their offense the needed boost for a championship.

"Guys just kept coming, kept rushing, kept doing their thing," lineman Aziz Shittu said. "Eventually, we got our hit in."

This was supposed to be the rebuilding year for Stanford's defense, and it ended up being exactly that -- but with a triumphant finish. The Cardinal now look forward to practices for the Rose Bowl Game Presented by Northwestern Mutual, where coaches can further develop the young crew.

There's a promising core to build around: A handful of freshmen earned trial-by-fire experience in the secondary, while rushers like Joey Alfieri and Mike Tyler emerged over the course of the year. Of course, there's also Thomas, the specimen who'll anchor the Stanford defensive line of the future.

"Kid's a freak," Shittu said. "I'm really excited to see what he can do with the rest of his career here."

Back in August, Shittu said that Stanford's defense was a work in progress, but that it would end up "being a force to be reckoned with" in 2015. His words became prophetic on that one third-quarter play, when Martinez jarred the ball loose from Kessler and Thomas ran with it to a championship.

The cliche lived.