KANSAS CITY, Mo. -- Washington State head coach Mike Leach watches as much pro football as he can. And Leach can't remember the last time he failed to see a team using concepts and sometimes exact plays from the Air Raid offensive system he became famous for first at Texas Tech and then at Washington State, a system he has used even before that when he was an offensive coordinator.

"I'm watching a game and all of a sudden I see something we ran just the other day," Leach said. "It's every team and every game now."

Two of the biggest practitioners of the college concepts meet Sunday night, when the New England Patriots host the Kansas City Chiefs. Expect a lot of shotgun formations, spread fields, option plays and other college concepts.

It hasn't always been that way across the league, though, with coaches criticizing quarterbacks from college spread offenses.

But while others complained about the difficulty of teaching a spread quarterback an NFL offense, Chiefs coach Andy Reid embraced it. Last year in the first round the Chiefs drafted Patrick Mahomes, a spread quarterback in college at Texas Tech who rarely took a snap from under center.

"I think the one great thing about college football today is that these kids are throwing the ball," Reid said. "So it used to be you're getting kids that weren't throwing the ball, and we complained about that as coaches. Heck, now they're throwing the ball and we're still complaining. I'm going, 'Hey, bring it on.'

"We went through the option phase and then the I‐formation phase. Now guys are spreading them out and they're throwing it. That to me is a positive. They're having to read things, get the ball out of their hand, move in the pocket a little bit and learn things they would have otherwise had to learn here. I think they're a step ahead, although it's a different system.”

The Patriots have been using the spread for years as well. Last year's Super Bowl between the Patriots and Eagles featured two teams heavy into college concepts.

The fast pace, as the teams ran 143 plays and totaled more than 1,151 yards, and the final score -- 41-33 in favor of the Eagles -- showed it.

"We've done it here off and on for a long time," Patriots offensive coordinator Josh McDaniels said. "Honestly, I think every game is its own game and every opponent, as you study and prepare to play against the next opponent, you're really looking at the best ways you can to try to move the football and be productive on offense and score. And so, some weeks, that may or may not be the best thing to do.

"Spreading teams out has become much more the norm in the National Football League than it isn't, and we certainly want to be able to do a lot of things well and right offensively. When we choose to do that, there's a lot of people that have to do a lot of things right in order for it to go and be productive. When you spread out, the offensive line doesn't have a lot of people in there near the tackles. You sometimes tell the defense what types of protection systems you're using. So, there's a lot of things that go into it."

Reid also brought his offensive system to Mahomes as opposed to making his quarterback fit into the offense he was operating. Mahomes, for instance, in his first season as the starter has been under center for only 68 snaps, the fourth-lowest total in the league.

With the proliferation of college games on TV and easy availability of college video, teams can watch a play or see a concept they want to borrow and have it in their playbook within days. The Chiefs, in fact, have done just that.

Offensive coordinator Eric Bieniemy described how the Chiefs go through their usual Saturday night offensive meeting, when the coaches fine-tune the game plan and go through any other eve-of-the-game scenarios. And often during those meetings they're also watching college football.

"While we're having those discussions, whatever Saturday night football game is on, we're watching and saying, 'Hey, did you see that play?'" Bieniemy said. "You're looking at all these different college games and you see certain offenses and seeing teams doing certain things. You can't help but notice some of the ingenuity that's being used at that particular level.

"It has an influence. Everybody's looking at the college game. At the college level, they're making sure you have to defend every inch of the grass. We want [opposing defenses] to defend every blade of grass."

Reid was an early innovator. He used some option plays when he coached the Philadelphia Eagles, first with Donovan McNabb at quarterback and later with Michael Vick. Reid was forced to use the shotgun formation for the first time in 2005, a year after the Patriots beat the Eagles in the Super Bowl by consistently blitzing up the middle with McNabb constantly under center.

"The shotgun was one of the solutions for that," said Brad Childress, then the Eagles' offensive coordinator. "You didn't want the quarterback to be standing next to the line of scrimmage."

Reid's idea was to find plays and concepts his quarterback would be most comfortable with. He increased those things in 2013, when he joined the Chiefs and acquired Alex Smith as the quarterback. Reid even hired Childress as an assistant coach and gave him the title of "spread analyst."

Smith by that time was a veteran, but up to that point his greatest success had come in college at Utah, where he played in the spread for Utes coach Urban Meyer. The Chiefs with Smith became early NFL adopters of run-pass options, or RPOs.

"I went back and pulled all his college stuff [and found] out what he is most comfortable with," Reid said. "I know Urban Meyer ... kind of through all that conversation and film review, we gave [Smith] a handful of things and said, 'Hey, what do you think about this?' The longer he was with us, the more he had input to where, towards the end, he would tell you, 'I'm lukewarm on that,' or 'I love this,' type of thing.

"Now we were into the RPO stuff. So we started incorporating that in. I tried to find his best stuff, what he felt most comfortable with, and we started off with that and we put it in, and we just grew it from there."

It's difficult to predict where all of this is heading, but the spread is in the NFL to stay. Chiefs defensive coordinator Bob Sutton called defending the traditional NFL formations of two backs, two wide receivers and a tight end "batting practice." Things get more difficult when defenses are required to defend the entire field and deal with concepts like motion and misdirection.

Whatever NFL offenses come up with next, it probably will come from college coaches like Leach.

"The hardest thing in football isn't in getting a good idea, because there are good ideas everywhere," Leach said. "There are more good ideas than you could ever manage or have the privilege to run. The hardest thing is selecting the ones that complement each other and having the discipline to not do too much."