Boise State’s offense — at least the current golden era as the highest-scoring team in the country — traces its roots to Oregon in the late 1990s when Dirk Koetter and Chris Petersen spent time together on the Ducks’ coaching staff.

Now the “Boise State offense” is expanding its reach and stretching across the country.

While Petersen and first-year coordinator Robert Prince are adapting to new personnel in Boise, Koetter is running a version of it as the offensive coordinator of the undefeated Atlanta Falcons in the NFL.

Bryan Harsin (offensive coordinator from 2006 to 2010) is trying to install “the Boise State offense’’ at tradition-rich Texas.

And Brent Pease (offensive coordinator in 2011 after five years as wide receivers coach) has taken it to Florida in the mighty SEC.

Each has brought a different twist to the offense, but the success hasn’t changed. The four teams are a combined 21-3.

“How do you describe the Boise State offense? To me, when it’s at its best, how you describe our offense is we score points,” said Boise State offensive line coach Chris Strausser, who has spent 11 of the past 12 seasons with the Broncos. “It’s not West Coast. It’s not downhill run game. It’s scoring points. And those guys are scoring points, so yes, it is Boise State’s offense.”

‘ATTACK MODE’ IN THE NFL

The Falcons are sixth in the NFL in scoring (28.5 points per game) in Koetter’s first season. With fifth-year quarterback Matt Ryan and a wealth of weapons, Koetter is in an optimal spot after five years in Jacksonville.

“Matt wants to be in attack mode. Our head coach wants to be in attack mode. What a great situation for a play-caller when your boss and quarterback are telling you ‘let’s put the pedal down’ and you got the players to back it up,” said Koetter, Boise State’s head coach and offensive coordinator from 1998 to 2000.

Koetter said his current situation reminds him of his stint at Boise State, where as head coach no one questioned his aggressive calls and he had the players to execute them.

“Matt felt like it was time. He was ready to be put in that position where the game flowed through him. I agreed,” said Koetter, whose successful season will likely put him atop the list for coaching vacancies in the offseason. “We have the players around him and the protection around him to back that up.”

A NEW FORMULA AT FLORIDA

Koetter keeps in touch with those who followed him as Boise State offensive coordinator, the men who have overseen an offense that has averaged 41.3 points per game since 2000.

Koetter sent Pease a text message after Florida defeated LSU two weeks ago. The Gators pounded the Tigers with a relentless and simple rushing attack in the second half.

“Everybody thinks the Boise State offense is a bunch of trick plays, but Pease got LSU with counter and power,” Koetter said.

Said Petersen: “All the very good offenses, there’s a beauty in the simplicity of how they do it.”

At 6-0 and ranked No. 2 in the BCS Standings, Florida’s run-based attack is working just fine despite Pease’s search for balance. Florida ranks No. 14 in the country in rushing offense and No. 114 in passing. Last week, the Gators rushed for 326 yards and passed for 77 in a win over Vanderbilt.

“Whether that kid ends up throwing for 300 or rushing for a record like he does, I don’t care how it gets done as long as we’re productive with what we do and score points,” Pease said

That kid is 6-foot-4, 237-pound quarterback Jeff Driskel, who outran the Vanderbilt defense for a 70-yard touchdown en route to 177 yards rushing last week. Pease is calling for plays that he would not have considered with precision-passing Kellen Moore under center.

“I can guarantee you one thing,’’ said Pease, highlighting Moore’s excellent passing ability and lack of rushing skills. “We wouldn’t have been doing this with Kellen Moore running the ball. No way.’’

TRUSTING THE PROCESS AT TEXAS

Texas coach Mack Brown courted Harsin when it came time to rebuild the Longhorns’ offense. College football bluebloods have taken note of the offense on the blue turf, in large part because it is not the gimmicky, trick-play offense many believe it to be.

“They beat people with basic football plays, they just execute them better than anybody else,” Koetter said. “If you have good players and they are well prepared and out-execute the other team, you shouldn’t have to trick them. Sometimes teams have been fortunate that their shot plays or home run plays work. But it’s not always about tricking them. Most of those plays are calculated for a certain situation. You have the courage to call it.”

Harsin had the courage to call them in the 2007 Fiesta Bowl, still the signature moment for the program and the reason many equate the offense with trick plays.

Harsin, a former Capital High and Boise State quarterback, has not enjoyed the immediate success of Pease in his new role.

But the Longhorns, even after back-to-back losses to West Virginia and Oklahoma, are No. 10 in the country in scoring, averaging 42.5 points per game. A blowout loss to the rival Sooners has everyone searching for answers in Austin — even Harsin.

“The key to this whole thing is you have a process, you believe in the process, you stick to the process and you understand this process got you the wins. It also got you the losses,” he said.

“All right, well, why? Where in that process did we go wrong? Or were they just flat out better? In this game, things went wrong. So we go back and we trust in the process but we fix it, we tweak it, we tune it, we make sure that it’s evolving each week. That’s what we do.”

A ROCKY TRANSITION AT BOISE STATE

Boise State’s offensive production this year has sharply declined from where it has been. The Broncos rank 88th in the nation in total offense (370.8 yards per game) and 80th in scoring (25.2 points per game) with Prince calling the plays and first-year starter Joe Southwick at quarterback.

Koetter, who keeps tabs on the program and communicates with Petersen, doesn’t see reason for worry.

“Unfortunately for Joe Southwick, he comes in off the all-time winningest quarterback in college football history. It’s only natural that there was going to be some kind of letdown in the beginning,” Koetter said. “The more Joe gets to play the better he’ll do. ... Boise State will be back hitting on all cylinders at some point in the future.”

Brian Murphy: 377-6444,Twitter: @MurphsTurph