West Virginia head coach Dana Holgorsen developed the diamond set – an inverted wishbone with three running backs surrounding a quarterback in the pistol – in 2009 while he was the offensive coordinator at Houston. The scheme flourished at his next stop in Stillwater, Okla. in 2010 by utilizing talented wide receiver Justin Blackmon.
"We came up with the three-back system to isolate the outside guys," Holgorsen said in 2011. "It's easier for the quarterback to see if it's man, one-on-one coverage when they're all packed in as opposed to being spread out and those guys being able to disguise a bunch of stuff."
With the diamond formation cramming nine players into the offensive box, defenses are unable to disguise their coverages. Match the numbers in the box and the two cornerbacks are set up in man coverage. Blackmon's ability on the perimeter often forced defenses to play a safety over the top, creating a numbers mismatch at the line of scrimmage.
While Holgorsen created the set for passing purposes, Johnson went to work installing the new look to his run-heavy offense during the spring.
"[The diamond formation] gives you better angles sometimes, especially if you are trying to get linebackers," Johnson said earlier this week. "You have a little better run angle and you're running downhill, but it doesn't hit as fast. There are tradeoffs both ways. A lot of it depends on how the defense is playing."
Quarterback Vad Lee (15-of-27, 314 yards, 6 TD, INT) likely represents Johnson's best arm during his tenure in Atlanta. The red-shirt sophomore's throwing ability forces a defensive coordinator into what could be a no-win situation with his free safety.
Lee told the Atlanta Journal-Constitution that the diamond formation was "big time" and "pretty huge" in Georgia Tech's success against the Blue Devils. The Durham, N.C. native, who said working out of the shotgun allowed him to make better reads, completed 8-of-16 passes for 125 yards, four touchdowns and an interception and also rushed for 76 yards and a touchdown on Saturday.
The challenge of the diamond formation is that it allows the offense to outnumber the defense quickly on one side or the other once the ball is snapped, according to UNC associate head coach for defense Vic Koenning.
"You can rapidly get your opponents circled and get around the edge or you can kick guys out and go up the middle," Koenning said. "There's a ton of things you can do out of it."
And while Johnson may have sprung the formation on Duke, he didn't roll out the entire package. The sixth-year Georgia Tech head coach told reporters on Tuesday that he only ran three plays out of the diamond against the Blue Devils.
After preparing for Georgia Tech's standard offense during its bye week, North Carolina went back to work on Sunday to prepare for the new look. That may have been part of Johnson's plan.
"The more we get them to not focus on their fundamentals, the better for us," Georgia Tech B-back David Sims said. "With the diamond, just switching back and forth from the diamond to going under center and stuff like that, it really makes you have to focus in and make sure that you know your assignments, know your keys. That's some of the confusion that we want caused with it."
Even so, UNC's defense has experience working against the diamond in practice. The Tar Heels rolled out their version of the formation against Middle Tennessee two weeks ago.
"I actually prefer that they come out in that because it's more football to me," defensive tackle Tim Jackson said. "That's football. I actually prefer it, but they might not do it at all. But if they do it, I'll be ready for it."
To Jackson's point, there are no assurances that the Yellow Jackets will line up in the diamond this weekend. Johnson proved last season in Chapel Hill that his offense is plenty capable of scoring points without the new set.
"Will we see it Saturday?" Johnson rhetorically asked on Tuesday. "Maybe, maybe not. It depends on how they play."