Posted by ESPN.com's Tim Griffin

I’m starting a Monday post each week where I’ll assign a grade from the performance of each Big 12 team in the previous week. It will change from week to week and will have no correlation with the power rankings which will be more a judgment of the relative strength of a program.

But here’s a look at how I thought each Big 12 team performed in openers.

Missouri: A. The Tigers had the most solid performance of the weekend -- and maybe the most underrated one in college football. Blaine Gabbert was a first-game revelation. And where did that defense come from?

Texas A&M: A-minus. Coach Mike Sherman needs a bowl this season and Saturday’s outing was a good start. Maybe the “Wrecking Crew” defense is coming back as Von Miller leads the nation in sacks.

Baylor: B-plus. A fast start enabled the Bears to take Wake Forest out of their game. Sure, there were some late stumbles, but the Bears did enough to finish an opponent on the road. When’s the last time we saw that?

Nebraska: B-plus. I was most impressed with the way the Nebraska defense came up with turnovers. The Blackshirts gave up some yardage, but were playing a quarterback in FAU’s Rusty Smith who will be in the NFL next season. And the future looks extremely bright if the first-game performances of Rex Burkhead and Cody Green are any indication.

Oklahoma State: B-plus. I might be grading on the curve here, but after watching them Saturday, I think the Cowboys can play much, much better. Maybe it was because of Georgia. But the Cowboys’ offense and special teams -- two presumed strengths -- still could carry this team and they didn't show much. Bill Young gets my coach of the week award for his masterful job against Georgia, rebuilding the Cowboys' confidence after the first TD drive by Georgia to start the game.

Texas: B. The Longhorns gave up more points than they’ve allowed in an opener in 10 years and still won by 39 points. That says something, doesn’t it? And D.J. Monroe might end up being that threat in the backfield.

Kansas: B. Hard to get a gauge on the Jayhawks after their victory against Northern Colorado, considering the fearsome Bears have posted a 3-32 record for former Nebraska aide Scott Downing over the last three-plus years. We’ll get a better gauge this week at UTEP, particularly with Dezmon Briscoe returning to the receiving corps and the special teams.

Iowa State: B. Solid first game for Paul Rhoads, particularly considering his offensive coaches made makeshift adjustments after their headsets went out during the first half. Thank goodness for those unlimited cell phone plans. The Cyclones tackled better, although they still missed too many. And transfers Darius Reynolds and David Sims look like keepers.

Kansas State: C. The Wildcats’ special teams -- such a strength during the Ron Prince era -- nearly cost them big-time against Massachusetts. Fortunately for Bill Snyder, his defense mustered two big stops and his offense overcame two key turnovers by Carson Coffman. Special notice to Daniel Thomas who rushed for 104 yards and showed the athleticism expected when he arrived from Northwest Mississippi Junior College.

Texas Tech: C. Where were those blowout scores we’re used to seeing when the Red Raiders pummel some hapless FCS school? The fact that the mighty Fighting Sioux of North Dakota were within two scores for most of the fourth quarter wasn’t a good sign. And neither was Taylor Potts’ three interceptions.

Oklahoma: D. BYU is a good team and deserved to win. But the Sooners’ struggles with penalties and offensive sputtering in the red zone were likely enough to prompt even more discussion among Sooner offensive coaches than Sam Bradford’s injury. The offensive line’s play looked like something captured from a John Blake time warp. Was Stockar McDougle still playing for the Sooners and I missed it?

Colorado: F. Where do I begin? The Buffaloes were supposed to have a physical, dominating offensive line with heralded running back Darrell Scott as the key to their running game. After one carry against Colorado State, wonder if Scott is regretting he didn’t go to Texas? The Buffs looked slow and unorganized on offense and were repeatedly blistered by big plays on defense. Toss in a dropped TD pass and some late-game charity and the Buffaloes could have been beaten Sunday night by 20 points. And it won’t get any easier considering their short work week heading into the Toledo game.