For four straight games, Notre Dame has given up over 150 yards rushing.
But each of those four opponents had something in common - a power running attack using fullbacks and tight ends to clear out the smaller Irish front seven.
This week's opponent, Purdue, offers a different challenge. The Boilermakers run a spread offense, which features at least three wide receivers and a shotgun formation on most plays.
"They spread it around pretty good," Irish defensive coordinator Corwin Brown said. "They do a really good job of executing what they want to get done. It will be a good test."
And while Purdue has been effective running the ball this season - 202 yards per game - the Irish hope their 3-4 front will be better at stopping the Boilermaker's finesse game than it was at stopping the power games of Georgia Tech, Penn State, Michigan and Michigan State.
"It's different for us because we haven't played it this year," Irish linebacker Joe Brockington said. "It's a game of playing in space, and we just have to make tackles."
Brockington, who made two tackles last year against the Boilermakers, said defending the spread in the 3-4 is similar to defending it in the 4-3 defense the Irish ran last year.
"I don't think it's changed much," he said. "When it comes down to it, you still have to play in space and make tackles."
Fellow linebacker John Ryan said defending the run against a spread offense is harder because players have to play the pass first - and then react to running plays.
"You have to make your reads and get your drops in the passing lanes, but when it's a run, you have to read the run and come up and stop it," he said.
For this reason, defensive end Trevor Laws said the spread puts more pressure on the defensive line to get into the backfield.
"It's a little bit of a different gameplan. It's up to us on the defensive line to get pressure," he said.
The Boilermakers running game is lead by tailbacks Kory Sheets and Jaycen Taylor, who average around 150 yards combined per game this year.
"They're a good group," Laws said of the Purdue backs. "They all run hard. We have to keep the ball in front of us."
Purdue coach Joe Tiller has run a spread offense since he took the job in West Lafayette in 1997. Nicknamed "basketball on grass," the scheme was considered groundbreaking when it was seen outside of Flordia. Today, teams from Oregon to Florida run some form of the spread.
The offense has also evolved over time. When Tiller first started, it was mainly a passing offense, but teams have figured out how to run out of it, especially using counters, draws and options.
"If you say they're one-dimensional, because they're spread out so much, if you said all they did was throw it all the time, then you could try to just stop the pass," Notre Dame coach Charlie Weis said. "But they're averaging over 200 yards a game rushing as well."
Notre Dame has been successful defending the pass this year, allowing less than 50 percent completions and less than 120 yards per game, but Weis said if the Irish concentrate too much on stopping the pass, the Boilermakers will make them pay on the ground.
"They're a passing team first. I think they'll run it to make to keep you honest," he said. "That's why they get some of these gash runs they get."
