Notre Dame wasn't finding a way to introduce advertising signs on the sideline during Saturday's 28-3 win over Utah.
In the large signs that featured Gatorade and Double Mint Gum were part of the Irish's new offensive play calling system.
Irish coach Brian Kelly said Sunday that the team used the bye week to change how it's plays were signaled in because there was a fear that some of the signals could have been compromised and also to help freshman quarterback Tommy Rees process the plays quicker.
"It's late in the season, and we have a lot of eyes on us," Kelly said. "We are a team that signals in with no-huddle and later in the season, especially when you get a bye week, you get an opportunity to retool some of your information that you want to get out to your players.
"This was an opportunity for us to break some codes, if you will, relative to our signaling, change some things up. We felt like some of our signals were compromised. We felt like the pictures were a way for us to communicate effectively with all the players. Secondly, it was also an opportunity for us to get Tommy a way to put together a full concept without having to see all the signals."
The technique has gained fame this season as the No. 1 Oregon Ducks have used it to signal its plays.
Notre Dame's signs included images of Gatorade, Double Mint Gum, Curious George, a tree, the Notre Dame logo, a turkey, the Golden Dome and Rex Ryan.
"Each one of them has a significant meaning to tempo, play call and the package of concepts relative to the receivers. Each one of them has a separate meaning," Kelly said. "It's easy for them to pick up the concepts right away than have to wait on some longer signals. We used a lot of motion, and when you utilize motion you have a lot more signals. These concepts allowed everybody to be on the same page."