When it happened, I wrote off the Oklahoma Sooners.

Who wouldn’t after what transpired Oct. 3 in Ames? Iowa State pulled off a 37-30 stunner and handed Oklahoma its second-straight Big 12 defeat, leading many to believe the reign it had over the conference was long gone.

Well, here we are. A week-three rematch to decide the Dr. Pepper Big 12 champion. One program has been a blue blood for well over 30 years; the other is trying to prove the regular season was far from a fluke.

No. 6 Iowa State and No. 10 Oklahoma start off Championship Week on Saturday morning at 11 a.m. in Arlington, Texas, a game that is going to look very, very different than well over two months ago.

The Cyclones are turning into an offensive juggernaut — scoring more than 35 points in four of their last five games — all wins. The Sooners haven’t allowed an opponent to reach the 30-point threshold over the last five contests.

So, how will this game be decided? Here are my three keys to victory for both Iowa State and Oklahoma.

Iowa State

1. Don’t overthink the coverage

In most of the games this season, the Cyclones have been relatively fine when they drop seven or eight in coverage and just let their front three generate pressure.

And they have had success. Latrell Bankston’s sack in the Texas game was on a three-man rush; JaQuan Bailey, relatively quiet since his record-breaking game against TCU, will need to wake up.

But if Iowa State brings a blitz, relying on their secondary to make a play, that might not be the formula to victory. The Sooners, and really every opponent this year, have found ways to get 25-plus-yard plays consistently.

Cyclones defensive coordinator Jon Heacock just needs to keep it simple. Allow the defensive line to win the trenches and trust your linebackers and defensive backs to hold firm.

2. Let Breece Hall cook

Have you heard about Seattle Seahawks quarterback Russell Wilson cooking? Well, it’s time to transfer the knives and cutting board to the future All-American tailback.

I don’t think I need to explain how great the true sophomore is — that’s been hashed out and will continue to be hashed out — but I will say the following.

That Iowa State offensive line has been magnificent all season long. If Trevor Downing plays Saturday — he’s listed as questionable — I don’t think it helps. Yes, Downing is a tremendous talent, but the cohesion of that starting five has been what has allowed Hall to rush for over 1,300 yards and reach the end zone 17 times.

If Sean Foster, Robert Hudson, Derek Schweiger, Darrell Simmons Jr. and Jake Remsburg control the line, Hall will have yet another monster performance.

3. Win third downs offensively

Ranked as the 35th-best third down team in the country, Iowa State will need to continue to be efficient on third down to beat the Sooners twice in the same season.

Get quarterback Brock Purdy going with some designed runs, allow Xavier Hutchinson and Tarique Milton to get in some space with some out routes or just do some run-pass options.

Any way to keep the Oklahoma offense on the sideline, do it.

Win the time of possession battle, win on third down and that can lead to winning the Cyclones their first ever Big 12 title.

Oklahoma

1. Experience

It might be the most cliche item in this column, but it’s a straight fact.

The Sooners have been there, done that. Since the Big 12 returned to the championship game format in 2017, no one else other than them has won.

They know the atmosphere. Heck, Arlington has kind of turned into Norman-south for that fanbase. The Cyclones are the wide-eyed newcomer into an environment none of them have played in collegiality.

Lincoln Riley has made it a staple to get to this point, and no one has had an answer for him thus far. So long as Oklahoma stays the course, it should win its fourth-straight conference title.

2. Keep the yellow flags off the field

Oklahoma has been penalized 68 times in nine games. Only 19 other FBS teams have been flagged more. The 638 yards of penalties is the 15th worst in the nation.

During this current six-game winning streak, the Sooners have had an average of six penalties per game, amassing an average total of 66 yards. Only once have they been penalized more than 10 times in the streak.

It’s a decent sample size to look at. Neither side is going to play a 100 percent clean game, but it’s about who will avoid the dumb penalties and the ones that keep drives alive or are drive killers.

If the Sooners avoid that, it’s a step in the right direction.

3. Don’t hold back Spencer Rattler

Is Rattler better than Baker Mayfield, Kyler Murray or Jalen Hurts? No. Two of them won the Heisman Trophy, the other was a star in his one year in Norman.

But is Rattler capable of putting up numbers like the ones that came before him? Absolutely.

The redshirt freshman has stayed accurate since the loss in Ames, completing 65.6 percent of his passes with just three interceptions. If he can get those big plays Saturday like he did in the regular season, he’ll put up gaudy numbers.

If Riley plays it like he has the last three trips, Rattler will have no issues reaching the end zone with his arm and leg.