The wishbone led to the veer led to the flexbone led to Nebraska’s dynasty of the 1990s, and then the traditional option offense dropped off the map.

But for decades, starting in the 1960s and running through the turn of the century, option attacks could be found among scrappy upstarts and entrenched national powers alike. Then as now, talent was the deciding factor, followed by execution. Games between Nebraska and Oklahoma, for example, would be chess matches — full of moves, countermoves and halftime adjustments as the two rivals looked for weak spots against an opponent cut from a similar cloth.

College football’s current offensive spectrum looks like this: On one side the Air Raid, those pass-happy styles popularized by Mike Leach and his many coaching acolytes found in nearly every conference; and on the other those run-first, run-second and run-always systems now found at the three service academies and, in the one remaining outlier among the Power Five leagues, at Georgia Tech.

“Our offense comes down to toughness and grit,” said Army running back Darnell Woolfolk. “We’re obviously not the biggest team offensively, but we have the mental toughness to go in every play, to give it our all. We have great effort at every position on our team. I think it all just comes together well and it starts with our toughness.”

Georgia Tech coach, Paul Johnson, learned the wishbone in high school before tweaking and developing his style as an assistant coach at Georgia Southern, helping the Eagles win back-to-back Football Championship Subdivision national titles in 1985 and 1986. By the time his run as Hawaii’s offensive coordinator ended in 1994, he’d inspired two branches on his coaching tree, Jeff Monken and Ken Niumatalolo, to embrace the same approach.

Both would later join Johnson on his staff at Navy in 2002, with Niumatalolo serving as Johnson’s successor since 2007. Monken would be hired at Army in 2014, bringing two close friends with matching offensive visions into annual competition. On Saturday in Philadelphia, the Cadets will look to win their second in a row against Navy for the first time since 1996.

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And they’ll meet with one shared play at the root of their similar offensive playbooks: The quarterback will take a snap from under center and pause for just a beat, evaluating the three choices at his disposal — to hand the ball to the fullback, to pitch it to the running back or to keep it himself.

“I really think that’s what it comes down to, the execution of our assignments and the fundamentals and who does it best,” Monken said.

The ties that bind together Army and Navy extend beyond football — along with Air Force, the three service academies are wholly different from their Football Bowl Subdivision peers, for reasons easy to explain. Those similarities continue on the field, where the two rivals compete in college football’s most unique series: Army and Navy are essentially mirror images of one another, with parallel defensive styles and, most of all, a nearly carbon-copy approach on offense.

“From a base-philosophy standpoint, it’s the same offense,” Monken said. “When the ball gets snapped it’s just a fistfight for five or six seconds. They blow the whistle and then we do it again. We’ll do it all afternoon. The competitive spirit of every guy out there, regardless of what color jersey he’s wearing, is pretty incredible.

“We’re just preparing ourselves for a 60-minute slugfest. Saturday will tell the tale.”

There’s a primary reason why Army and Navy are defined by this option offense: it evens the playing field. A few decades ago, this offensive style would’ve been the norm, and running the scheme would not alone have separated one program from another. There was no element of surprise.

To be successful at Army and Navy demands being different. Navy has known this for more than a generation, and wisely decided to maintain the progress made during Johnson’s tenure by promoting Niumatalolo a decade ago. In hiring Monken, the Cadets opted to embrace Navy’s blueprint in an effort to stem a parade of failed coaches and offensive styles.

Now far less prevalent, the option-based scheme wobbles defenses more accustomed to a new era of offensive styles — even if the up-tempo approach now in vogue across college football has roots in the option, as the latest evolution in the offensive style. Boiled down, running the offense can help Army and Navy minimize the ever-present gap in talent and size.

And that’s not just on offense. For Army and Navy, one of the secondary benefits of the option can be found on the defensive side of the ball, thanks to an ability to control the football and the time of possession — Navy ranks first in the nation in the latter category, averaging possession for nearly 37 minutes, and Army ranks fourth. There is no defensive scheme to match the uniqueness of the option system, so the best hope for both defenses is to simply keep the opposing quarterback on the sideline.

"It gives us a chance to compete," Niumatalolo told the Associated Press.

The script changes when the two teams meet in their annual rivalry, dominated in recent years by the Midshipmen. There is no element of surprise, no unfamiliarity and no catching the opponent unaware, unless one offense rolls out a never-before-seen quirk — as Monken admitted, “We’ve got to have some wrinkles.”

Against every opponent, the keys for Army and Navy are technique and execution; those factors will be multiplied exponentially on Saturday. No team can be perfect, even one that practices the same series of plays and formations so often from one season to the next that it can be like muscle memory. Success isn’t measured by one 40-yard run but by a dozen 4-yard runs, over and over again.

“We don’t really reach out to anything new,” said Army running back John Trainor, adding that a successful option attack is about “playing fast and with good fundamentals.”

Any differences between the two offenses is predicated on personnel. Navy quarterback Zach Abey uses every ounce of his 215-pound frame to grind out yards between the tackles. His counterpart, Army senior Ahmad Bradshaw, is a little shiftier and more explosive, as seen in his pair of 200-yard rushing performances in November. Army might block one play a little differently; Navy might use a similar blueprint on a specific snap but add a subtle difference, one perhaps only Army’s coaching staff would notice.

Going to the air is rare; neither team has attempted 100 passes on the season. Army has won games this season without attempting a pass.

But both teams always revert to basics. They know the score: Army does what Navy does and vice versa. Technique and the ability to execute without any major missteps will dictate the result when two programs built and maintained in a mirror image meet in college football’s national rivalry.

“When we are scheming against those guys, there’s just only so much we can do,” Monken said. “We can’t change our defense. We can’t change our offense. We’ve got to do what we do best and hope it’s good enough.”