Each week, we’ll take a look at the credible and not-so-credible threats to the SEC’s playoff aspirations, based on the now-retired Homeland Security Advisory System. (Here’s a longer explanation.)

This weekend’s main casualties: Southern California, Virginia Tech and Louisville.

There are now nine one-loss teams in the AP Top 25.

Some already are predicting chaos for the third and fourth College Football Playoff spots, but I see a different picture through three weeks. The SEC looks treacherous, with half the AP Top 10 in one division. The Pac-12 appears tough. But outside those two conferences, the number of legitimate CFP contenders is short and distinguished, with manageable schedules.

Outside determining the Pac-12 and SEC champions, I expect the list of contenders to remain pretty stable.

RELATED: Kirk Herbstreit’s top four teams fluctuate after SEC shakeup

Scanning The Good Guys: The SEC went 8-1 in non-conference games, dropping the Tennessee-Oklahoma contest. But the most significant outcome of Week 3, of course, was South Carolina’s 38-35 win against Georgia. The Bulldogs (1-1, 0-1) got hype as the SEC’s most likely College Football Playoff entrant after bulldozing Clemson in Week 1, while much of the nation wrote off the Gamecocks after a 24-point home loss to Texas A&M. Missouri and to a lesser extent Florida still are in play for the unpredictable SEC East, but the SEC West holds the conference’s key to the Playoff.

Now for the terrorists.

THREAT LEVEL: SEVERE

Severe risk of terrorist attacks.

Oklahoma: The Sooners are the most balanced team in college football right now. OU gave a business-like performance against Tennessee. With Texas (1-2) losing again, Oklahoma State losing its quarterback and no conference championship game, Oklahoma’s schedule looks more manageable by the week. Bob Stoops now is 24-7 against current SEC teams, a well-circulated stat Sunday afternoon. It won’t be a shock if OU and Stoops get another SEC foe in the national semifinals or finals.

Oregon: The Ducks trailed Wyoming, 7-0, after the first quarter and led 27-7 at halftime. Sure, Baylor can score quickly, and Texas A&M’s efficiency makes everyone jealous. But Oregon still holds the highest “don’t go to the concession stand or you may miss three touchdowns” quotient. Oh, and that Marcus Mariota guy quietly has completed more than 70 percent of his passes for 11.4 yards per attempt. While averaging 7.8 yards per carry. Oregon is a rich man’s Virginia Tech in that we’re perpetually waiting for the sudden stumble. But the Ducks have the pedigree and pole position in the Pac-12.

THREAT LEVEL: HIGH

High risk of terrorist attacks.

Florida State: Last year’s Week 4 Associated Press Poll featured 60 first-place votes. Fifty-nine of them went to Alabama and one went to Oregon. This year’s Week 4 AP Poll? Still 60 first-place votes. The No. 1 Seminoles claim 37 of them. Oregon (17), Alabama (1), Oklahoma (2) and Texas A&M (3) split the remaining 33. Translation? There’s not a clear No. 1. So don’t let FSU’s ranking fool you. The defense has major question marks, and that was before a rogue The Citadel offensive lineman singlehandedly tire-ironed the defensive line. The schedule also looks tougher in 2014, with a revenge-minded Clemson up next.

Baylor: The Bears launched a stretch of four road games in five contests Friday with a cool 63-point output at Buffalo. Then the team plays in its gorgeous new home stadium in four of its last five regular-season games. The exception? Baylor travels to Norman, Okla., to face the Sooners on Nov. 8. The young Bears defense gave up its first three touchdowns of the season, but has time to incubate yet, and Bryce Petty (back) appeared healthy after a worrisome and obscure back injury kept him out last week. This team is built to mow through mediocre opponents, but isn’t a severe threat until it performs better against elite competition.

THREAT LEVEL: ELEVATED

Significant risk of terrorist attacks.

BYU: No way the Cougars legitimately enter the College Football Playoff conversation, even if they go undefeated. Right? … Right? The answer is yes, but there’s a two-second pause that wasn’t there a week ago. BYU’s schedule isn’t intimidating. Games at UCF and at Boise State would be significant tests in previous years, but the Knights and Broncos already have lost a combined three games, including two to SEC schools. There isn’t as much traffic in front of the Cougars as I expected through three weeks. Wins against Texas and Houston (Friday) got some attention, and with quarterback Taysom Hill a potential Heisman finalist, the team could become a slight reach of a topic on a show like Around The Horn: “Does BYU deserve a CFP spot?”

THREAT LEVEL: GUARDED

General risk of terrorist attacks.

Pac-12 South: Quarterbacks Taylor Kelly (Arizona State) and Brett Hundley (UCLA) each got hurt Saturday, with the Bruins collecting a third consecutive one-score win. The Sun Devils are “very concerned” with Kelly. Hundley’s elbow injury looked troublesome, but reports early Sunday morning called it a slight hyperextension. Hundley may even play Saturday against ASU, but his Heisman chances already are dwindling. Meanwhile, with UCLA continually dodging bullets, Arizona State without perhaps its most important player for a significant amount of time and USC falling in a shocker at Boston College one week after ending Stanford’s 17-game home win streak, the Pac-12 South isn’t nearly as intimidating as it once looked. But UCLA still could revive, and USC has yet to play a conference game.

Michigan State: The Spartans remain ranked just outside the Top 10 despite an early-season loss and despite playing in the worst power conference in America. The Big Ten is practically begging the College Football Playoff committee to look elsewhere (see below), but Michigan State is good enough to regroup, get on a roll and slide up a category or two on our modified Homeland Security Advisory System.

THREAT LEVEL: LOW

Low risk of terrorist attacks.

Big Ten: We try not to pick on the destitute and needy. It’s a societal code of ethics. But sort of like the snot-nosed kid who insists on pulling pigtails at recess, the Big Ten hasn’t left us much choice. Let the results speak for themselves: Iowa, a Top 25 team to some before the season, lost to Iowa State. Unranked Washington blasted Illinois by 25. Maryland lost to Big 12 “power” West Virginia. TCU embarrassed Minnesota, 30-7. Oh, and Indiana lost to Bowling Green. That’s the third Big Ten loss against a MAC opponent in two weeks.

South Florida: After a 2-10 finish in coach Willie Taggart’s first season, the Bulls dumped the offensive coordinator, then managed to sneak past the Western Carolina Catamounts to open 2014. But USF lost to Maryland despite a plus-five turnover margin (!), then allowed a bad N.C. State team to demolish them, 49-17. Oh, and Wisconsin and East Carolina loom.

Georgia Tech: Once a legitimate Top 20 program, Paul Johnson’s Yellow Jackets nearly pulled a Florida and escaped Saturday’s game against Georgia Southern with a late touchdown. The team is 3-0, thanks to unimpressive wins against Wofford and Tulane. But with Virginia Tech, Miami, Duke, North Carolina and Pitt on deck, Tech may be in danger of missing a bowl game by Halloween.

Troy: A repeat visitor to our low-level threat list, the Trojans followed a 38-point loss to UAB with a respectable defeat to Duke. Then Abilene Christian of the Southland Conference clipped them at home, just before facing Incarnate Word and Houston Baptist. Meanwhile, Troy gets to travel to an angry Georgia on Saturday.

Kent State: Ohio State shed some frustration against the Golden Flashes (0-3). As if the 66-0 score wasn’t enough, the Buckeyes heaved a long pass on the game’s final play with the clear intention of adding another touchdown. With road games against Virginia and Northern Illinois on tap, Kent State, which ranks 125th in rushing yards per game and 127th in points per game (9.0),  doesn’t have much hope of avoiding an 0-5 start.