The 2019 college football season started with the presumption that this year would be an extension of the Alabama-Clemson rule of power that has defined much of the young College Football Playoff era. Two months from now, we could be right back where we started. But if the first half of the season has shown us anything, it's that the national championship picture has more players than can fit in the frame. 

Not only has No. 4 Ohio State emerged as one of the most impressive teams in the country, No. 5 Oklahoma has revamped its offense in the image of Jalen Hurts and appears just as playoff ready as any of the Baker-led or Kyler-led teams. Speaking of revamped offenses, it's No. 2 LSU, not Oklahoma, leading the nation in scoring. The Tigers have a team that's capable of going into Tuscaloosa, Alabama, and knocking off the No.1  Crimson Tide. 

The first seven weeks have shown us how wrong we were about the "Alabama, Clemson and everyone else" mindset. In addition to naming some CBS Sports Midseason All-Americans and getting a second chance at our playoff and end-of-season predictions, here are seven storylines to follow over the second half of the season.

SEC race heats up

The two biggest remaining games on the SEC schedule will be played in consecutive weeks: No. 9 Florida and No. 10 Georgia dueling on Nov. 2 followed by No. 2 LSU at No. 1 Alabama on Nov. 9. But those are far from play-in style contests for the SEC Championship Game, and in the case of Alabama-LSU, the loser is not necessarily eliminated from College Football Playoff contention. While Alabama, LSU, Florida and Georgia are the headliners of this year's SEC title race, the team that will have arguably the most influence is the one that plays all four: No. 11 Auburn

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Auburn is already 0-1 against that group following its loss to Florida, but it has LSU coming up on Oct. 26 in the SEC on CBS Game of the Week and hosts both Georgia and Alabama in Jordan-Hare Stadium two weeks apart in November. Any of those games could potentially be wins for the Tigers, bringing all kinds of tiebreaker scenarios into play for both division races. If Auburn gets frisky and wins all three, it will find itself back in the SEC Championship Game for the second time in three years. If the Tigers  lose all three, we remain with those early November winners facing off in Atlanta ... and perhaps heat back on coach Gus Malzahn.

So you think the SEC title race car is full with five major players? You forgot about the Tigers in the back. No. 22 Missouri is creeping up into the picture with no conference losses to this point (2-0). It sits just one Florida or Georgia win away from threatening to steal the SEC East crown from the winner of the World's Largest Outdoor Cocktail Party. Mizzou plays at Georgia the next week and then hosts Florida the following week. As it stands, Missouri is in the midst of an appeal process to try and get its postseason ban overturned so that it might be able to play the SEC championship, but it's going to have a say who wins the SEC East on the field one way or another. 

Jalen, Joe, Justin and Tua 

The names of the Heisman Trophy frontrunners -- Jalen Hurts, Joe Burrow, Justin Fields, Tua Tagovailoa -- have the makings of a great boy band with Alabama's quarterback as the bad boy. In reality, it's LSU's QB who is bringing the most swagger, experience and braggadocio to the conversation while the even-keeled Tagovailoa probably gets to sing lead on the sweeter soft songs. I'll save these boy band comps for my future Heisman House pitch because it's far more productive to celebrate and acknowledge the elite level of play we've seen from all four of these quarterbacks. All four are leading national championship contenders, and it's not crazy to think that all four could end up both in the College Football Playoff and as Heisman Trophy finalists. Check out these FBS rankings.

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  • Passer rating: Burrow (1), Hurts (2), Tagovailoa (3), Fields (6)
  • Total offense yards per play: Hurts (1), Tagovailoa (2), Burrow (3), Fields (18)
  • Yards per play: Hurts (1), Burrow (3), Tagovailoa (4), Fields (11) 

Fields, Ohio State's signal caller, trails the other three not only in many statistical categories but also in experience, age and playing time. But that could work in his favor if he continues to improve with every week and shines bright late in the season when Heisman Trophy voters start to get serious about their ballot. Tagovailoa was considered the frontrunner for much of last season before injuries and some late-season stumbles opened the door for Kyler Murray's Heisman win, and Fields brings that same newness to the conversation that could help his chances in early December. 

And while we sit here at this midseason point of reflection, it's worth noting that three of the four quarterbacks mentioned here as the elite class of college football signal-callers are transfers in their second stop at a blue blood program. For all the cries from critics that suggest transfers in college football is an "epidemic," I ask what's so damaging about a trend that has allowed the most outstanding individuals in college football to all be successful at the same time, competing against each other not just for the title of QB1 but for Heisman Trophies and national championships. 

Clemson vs. Clemson 

Dabo Swinney is just like nearly every coach in the country when it comes to preaching the importance of playing to a program standard. But nearly every coach in the country would love to be in Swinney's position, where playing to Clemson's standard is the toughest challenge left on the 2019 schedule. Simply put: Clemson is Clemson's toughest opponent remaining in 2019. 

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The No. 3 Tigers' playoff pursuit will be painted as a breeze and their merit will be debated once the CFP Selection Committee begins to release its weekly rankings next week, but achieving a 13-0 record is going to be tremendous test of focus and mental toughness. There is no margin for error in the loss column because of the wide-ranging field of contenders and a schedule that might not have a single team in the top 25 of the CFP Rankings on Selection Sunday. The committee is tasked with choosing the "four best teams," so I think an undefeated ACC champion Clemson is a lock to make the playoff, but any one loss puts them in a far less exclusive club of contenders where the tie-breaking metrics might not work in their favor. But if Clemson plays to the Clemson standard in each of its remaining six regular season games and in the ACC Championship Game, it will be back in the playoff for a fifth consecutive season. 

Ohio State will need to win with physicality

Once opponents get into the flow of a game against Ohio State and show their cards, the Buckeyes offense begins to operate with a precision that attacks weaknesses and uses explosive plays to put their foes in a hole that can seem inescapable. But we've seen the flash and dash of Ohio State's talent show out in the early part of the season before, and we know the real test of this team's national title contention will be its response when efforts to dictate pace and style are thwarted by Big Ten opponents. Ohio State has made winning look easy through the first half of the season, but history tells us that if the Buckeyes are going to make the playoff and contend to win it all they are going to have win ugly. 

The best sign for Ohio State's ability to win with physicality and toughness has been the play along the offensive line. It's a position group that lost four starters from a year ago but took steps forward in terms of production. They're getting great push at the line of scrimmage and reaching the second level of the defense to spring J.K. Dobbins and Justin Fields for long gains that have contributed to the Buckeyes carrying top-five national rankings in rushing yards per game (288.5, No. 3) and yards per attempt (6.18, No. 4). 

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With games against No. 6 Wisconsin, No. 7 Penn State and No. 16 Michigan all left on the schedule, Ohio State will be lured into playing a more gritty low-scoring style in order to win the Big Ten. But thanks to improvements along the offensive line -- and a defense that has proven to be elite at creating havoc and turnovers -- they appear well-suited for the challenge. 

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There are other Big Ten playoff contenders, too

In just five years of the College Football Playoff, we've already had one instance of a conference putting two teams in the final four. Talk of two SEC teams making the playoff has been a part of the conversation ever since Alabama and Georgia played their overtime thriller in Atlanta, but in 2019, we have the potential not only to see two SEC teams make the playoff but two Big Ten teams as well. The biggest reason for projecting that possibility? Wisconsin is one of the most dominant teams in the country, and Penn State seems to be getting better every week. 

Now anytime we've had a crowded group contenders within power conferences, the (correct) point to make is that these teams play each other and it will all be settled on the field. But Alabama's inclusion in 2017 when it didn't make the SEC title game -- and then proceeded to win it all -- shattered the prior assumption that the CFP race starts with conference title races. If the committee decides that a one-loss Wisconsin or Penn State (or Ohio State for that matter) is one of the four best teams in the country, than it's going to get in, regardless of its conference championship status. 

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Will the CFP be a SEC-Big Ten challenge? Doubtful. Clemson, Oklahoma and even No. 12 Oregon (more on the Ducks below) are too well-positioned in the playoff race to all end up at No. 5 or lower in the final rankings. But the strength of contenders at the top of the Big Ten has made it worth considering that the SEC isn't the only league that can get two in the playoff. 

Oregon is keeping the Pac-12 in the playoff race

First, the loss of Jacob Breeland is a huge bummer and massive setback for the Ducks' offense. Breeland was their best red zone receiving threat and one of the best tight ends in the entire country. You don't lose a player like that for the year and move forward without a slight downgrade. But even after adjustments, Oregon remains the best team in the Pac-12 and statistically one of the nation's superior defenses. The Ducks rank No. 4 nationally in yards per play allowed (3.94), No. 2 in pass efficiency defense and No. 1 in opponents' red zone touchdown rate, allowing just two touchdowns on 14 attempts. They take pride in bowing up when it counts the most, and it's a big reason why one the season Oregon is allowing just 8.7 points per game (No. 3 in FBS).

So while Justin Herbert remains one of the top quarterback prospects for NFL Draft folks, the identity of Oregon's playoff-contending team is with its defense and in the trenches on offense. The days of finesse and speed -- though don't get it twisted, Oregon will still leave opponents in the dust -- left room for a late-season loss if the Ducks got caught in a rock fight. This year that's the kind of game that Oregon welcomes and wins. If you haven't gotten a chance to see this group win with its defense, check out Saturday's colossal Pac-12 North showdown with Washington in Seattle. It's the game of the year in the division and one that will test Oregon's ability to crash the playoff. 

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Boise State vs. Appalachian State vs. the AAC

After two years of UCF not only pulling away from the rest of the Group of Five teams but campaigning for inclusion in the College Football Playoff, the second half of 2019 will include a wildly intriguing race for the New Year's Six bid for the Group of Five conferences with nearly a dozen teams contending to be the top-ranked conference champion in the committee's final rankings. Part of what's made this year's Group of Five picture so compelling is strong early season showings by the AAC, Mountain West and three-time defending Sun Belt champion Appalachian State. 

No. 14 Boise State is the early frontrunner, and its case is bolstered not only by a win at Florida State but the opportunity to win the MWC in a year when the league has already totaled nine wins against Power Five opponents. The potential pitfalls for the Broncos will be on the road as Bryan Harsin's team will play four of its final six games away from the friendly confines of the Smurf Turf. 

Should Boise stumble, the door is open for the AAC champion in a year when the field of conference contenders has never been deeper. No. 21 Cincinnati's win against UCF opened up the AAC East race, which also includes a 5-1 Temple team that's got wins against Maryland, Georgia Tech and Memphis on its profile. Things get even more tricky in the AAC West, where 6-0 SMU, currently ranked No. 19, is the frontrunner but 5-1 Tulane is also unbeaten in conference play. Memphis, whose only loss in AAC play is out of the division against Temple, gets both of those teams at home, starting with Tulane this Saturday night. 

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The dark horse here is No. 24 Appalachian State, which appeared in both the AP Top 25 and Coaches Poll this week. The Mountaineers have already won one of their toughest regular season games on the road against Louisiana and also have a road Power Five win on their resume after taking down North Carolina on the road. The key to App State's New Year's Six contention lies in its Nov. 9 trip to Columbia to face South Carolina, where it can add yet another Power Five win and see its stock soar heading into the home stretch of Sun Belt play.