Which teams could throw a wrench in the plans of 2018's playoff favorites the way Iowa did to Ohio State last fall? With March Madness in full swing, we're already looking ahead to the road to December's final four.

With the deadline for submitting NCAA tournament brackets fast approaching, you probably have an idea which team (or teams) you’ll be penciling in as spoilers. St. Bonaventure? Davidson? Loyola-Chicago? One of the country’s top teams is bound see their title hopes dashed long before the Final Four, and those upsets often create the tournament’s lasting images.

In college football, we don’t get nearly as much sanctioned postseason mayhem, but there’s plenty of chaos involved as the field of College Football Playoff contenders narrows over the course of the fall, whether it’s a rusty early-season loss or a late-year stumble that looms large. Which overlooked teams are in position to foil the plans of playoff hopefuls in 2018, following in the footsteps of Iowa in 2017, Pitt in 2016, Northwestern in 2015 and West Virginia in 2014? With that in mind, we embarked on a search for potential playoff bracket–busting upsets this fall.

Appalachian State (vs. Penn State, Sept. 1)

For the past two seasons, Appalachian State has opened the season against a top-15 team: Georgia in 2017, Tennessee in 2016. The Mountaineers lost both matchups, but they scored more points on Georgia than four of the Bulldogs’ other 2017 opponents did and took the Vols to overtime. It will be the 11-year anniversary of the day App State (then playing in the FCS) knocked off No. 5 Michigan in Ann Arbor, but you don’t need to go back a decade to see why this game has opening-weekend upset potential.

Over the past three seasons under coach Scott Satterfield, Appalachian State has averaged 10 wins a year and gone 3–0 in bowl games, never finishing lower than second in the Sun Belt. Sure, its strength of schedule—apart from the annual top-25 matchup—leaves something to be desired, but Satterfield’s team is rarely trounced, and Penn State will still be negotiating its identity in a post-Saquon Barkley world.

Beaver Stadium would be enough to overwhelm many a lower-tier nonconference opponent, but since moving up from the FCS ranks in 2014, the Mountaineers have played at Michigan, Clemson, Tennessee and Georgia. They are no strangers to the most intimidating stadiums in college football, and stranger things have happened in Week 1 than a Sun Belt team upending a Big Ten opponent. A loss would leave Penn State a long road back to playoff contention. The Big Ten East has been known to cannibalize itself at the top, with Ohio State securing a playoff nod ahead of Penn State, Michigan State and Michigan in three out of four years of the playoff era, and all four teams expect to contend once again. Starting the year with a nonconference loss would all but guarantee Penn State would need to run the table against Ohio State, Michigan, Michigan State and cross-division opponent Wisconsin, which is almost certain to be the best team in the Big Ten West again next year.

Baylor (vs. TCU, Nov. 17)

A season ago, Baylor had its worst year this century—the last time the Bears finished with just one win was in 1999—but the Bears lost several close games along the way. By Pythagorean wins, which examine points scored and allowed to estimate the number of games a team should have won, Matt Rhule’s first team played to the level of a 3–9 team, which is hardly great but still sets the table for regression. For that reason, along with a 2018 recruiting class that landed among the top 30 in the 247Sports Composite rankings, it’s not hard to see Baylor as a potential Big 12 spoiler next fall. The Bears aren’t far enough into their rebuild to contend, but they are certainly far enough along to upend the conference race, as they nearly did when Oklahoma came to Waco last September.

TCU has won the past three meetings, and the Horned Frogs look like the Big 12’s best shot at a playoff spot outside of Norman. TCU’s schedule is tough, with a Sept. 15 home game against Ohio State (which could earn it some major points with the playoff committee) and a visit from Oklahoma on Oct. 20. By the end of the season, TCU could have little wiggle room to keep its playoff hopes alive, and Baylor could be easy to overlook with Oklahoma State the next weekend and the Big 12 title game the following Saturday.

Purdue (vs. Ohio State, Oct. 20; vs. Wisconsin, Nov. 17)

Purdue will have two realistic shots to play spoiler next fall, when the two teams that met in last year’s Big Ten title game come to West Lafayette. A season ago, Purdue went 7–6 with a Foster Farms Bowl win over Arizona that secured the Boilermakers’ best record since 2011. After improving from 1–8 in conference games in ’16 to 4–5 last year under new head coach Jeff Brohm, it’s reasonable for fans to expect another winning year even though the road to another bowl is even tougher.

Brohm has yet to face Ohio State, but Purdue put up a solid performance against Wisconsin in last season’s 17–9 loss in Madison. And as a rash of quarterback injuries held back the early returns of Brohm’s offensive overhaul, the Boilermakers found surprising success on the defensive side of the ball. With both David Blough (dislocated ankle) and Elijah Sindelar (torn ACL) set to return by the fall, it’s not unreasonable to expect Purdue’s offense to translate continuity into marked improvement on the side of the ball Brohm has specialized in throughout his career. A Boilermakers win in either of these games would likely knock the loser out of the playoff hunt.

South Carolina (vs. Georgia, Sept. 8; vs. Clemson, Nov. 24)

South Carolina was another pleasant surprise in 2017, improving to 9–4 from 6–7 the previous year and making it two bowl trips in two seasons under Will Muschamp. Although they may have an outside shot at sneaking into the SEC championship game, the Gamecocks won’t figure into the playoff conversation. They do, however, have two prime opportunities to play spoiler: their SEC opener against Georgia and their season finale against Clemson. Beating the Bulldogs would certainly put South Carolina in the SEC East driver’s seat, but it would also severely damage Georgia’s chances at back-to-back playoff berths, forcing the Bulldogs to be perfect the rest of the year—against a loaded slate that includes LSU and Auburn and (presumably) Alabama in the SEC title game, should it get that far—to have a shot.

Clemson, meanwhile, could very well be undefeated going into its regular-season finale against South Carolina. It travels to Texas A&M in Week 2, at which point the Aggies should still be settling in under new coach Jimbo Fisher. Losing to South Carolina so late in the season would be a bad look for Dabo Swinney’s team at a bad time, and if the Tigers enter Thanksgiving with a blemish on their record, their in-state rivals might have what it takes to finish them off.

Washington vs. Washington State (Nov. 23)

Both Washington and Washington State have taken playoff hopes into recent Apple Cups, but by the end of last season the Pac-12 North had played itself out of playoff contention. If one or both teams are still alive for the conference title or the playoff on Black Friday, the spoiler potential will be high in Pullman. Washington State has the easier path to this game—its nonconference opponents are Wyoming, San Jose State and Eastern Washington, while the Huskies kick off the season against Auburn in Atlanta—but Washington’s roster is built to play for a championship in quarterback Jake Browning’s final year of eligibility. Assuming one or both of these teams can beat Stanford, the Apple Cup should matter, and if one team is out of the running by late November, it can take solace in the fact that anything can happen on the Palouse.