If you're looking for a week in which the projected College Football Playoff teams could change, Week 13 is it.
The quartet of teams expected to participate in the playoff after Week 12 face rivalry games, with Michigan taking on the most difficult task at Ohio State.
One loss by a team in the Top Four will alter the postseason landscape and spark up the discussion about which program belongs in the playoff in place of the side that was upset.
However, until Alabama, Clemson, Notre Dame or Michigan show a set of true weaknesses over four quarters, it's hard to see the upset scenario come to fruition.
College Football Playoff
Cotton Bowl (December 29): No. 1 Alabama vs. No. 4 Michigan
Orange Bowl (December 29): No. 2 Clemson vs. No. 3 Notre Dame
New Year's Six
Peach Bowl (December 29): Penn State vs. Georgia
Fiesta Bowl (January 1): Oklahoma vs. Florida
Rose Bowl (January 1): Ohio State vs. Washington State
Sugar Bowl (January 1): UCF vs. LSU
New Mexico Bowl (December 15): San Diego State vs. North Texas
Cure Bowl (December 15): SMU vs. Arkansas State
Las Vegas Bowl (December 15): Utah State vs. Arizona State
Camellia Bowl (December 15): Western Michigan vs. Appalachian State
New Orleans Bowl (December 15): Marshall vs. Troy
Boca Raton Bowl (December 18): South Florida vs. Florida International
Frisco Bowl (December 19): Toledo vs. Southern Miss
Gasparilla Bowl (December 20): Memphis vs. Florida Atlantic
Bahamas Bowl (December 21): Ohio vs. Middle Tennessee State
Famous Idaho Potato Bowl (December 21): Boise State vs. Eastern Michigan
Birmingham Bowl (December 22): Cincinnati vs. Arizona
Armed Forces Bowl (December 22): Temple vs. Army
Dollar General Bowl (December 22): Buffalo vs. Georgia Southern
Hawaii Bowl (December 22): Hawaii vs. Louisiana Tech
First Responder Bowl (December 26): BYU vs. UAB
Quick Lane Bowl (December 26): Northern Illinois vs. Georgia Tech
Cheez-It Bowl (December 26): Texas Tech vs. California
Independence Bowl (December 27): Miami vs. Tulane
Pinstripe Bowl (December 27): Purdue vs. Duke
Texas Bowl (December 27): Iowa State vs. Tennessee
Music City Bowl (December 28): Pittsburgh vs. Missouri
Camping World Bowl (December 28): Syracuse vs. Texas
Alamo Bowl (December 28): West Virginia vs. Utah
Belk Bowl (December 29): NC State vs. South Carolina
Arizona Bowl (December 29): Nevada vs. Louisiana
Military Bowl (December 31): Virginia vs. Houston
Sun Bowl (December 31): Oregon vs. Boston College
Redbox Bowl (December 31): Fresno State vs. Stanford
Liberty Bowl (December 31): Oklahoma State vs. Auburn
Holiday Bowl (December 31): Washington vs. Iowa
Gator Bowl (December 31): Michigan State vs. Texas A&M
Outback Bowl (January 1): Mississippi State vs. Wisconsin
Citrus Bowl (January 1): Kentucky vs. Northwestern
CFB Playoff Predictions
No. 1 Alabama vs. No. 4 Michigan
Alabama and Michigan weren't fully focused in Week 12, but they still battled through their shortcomings to remain in the playoff positions.
The Crimson Tide host Auburn in the Iron Bowl Saturday in a game that could be tricky, as the Tigers have won three of their last four games.
Even if Auburn gives Alabama its best shot, the Crimson Tide are in a class of their own, and it would take an implosion from within for Nick Saban's team to fall the week before the SEC Championship.
Next week in Atlanta is where things could get dicey for Alabama, as No. 5 Georgia has the potential to pull off a victory and force the playoff committee into a difficult decision to include Georgia and Alabama, or leave out a one-loss Crimson Tide team.
Alabama's likely opponent in the national semifinal is No. 4 Michigan, who has to pass an important test against Ohio State to reach the Big Ten Championship.
It's understandable why the Wolverines suffered a letdown against Indiana before pulling away Saturday because they were looking ahead to a winnable game against Ohio State.
The Buckeyes have been the dominant program in the Big Ten's marquee rivalry, but Jim Harbaugh's team has played significantly better this season than the Buckeyes, especially on defense.
A win over Ohio State would set Michigan up with a second clash versus Northwestern, who pushed the Wolverines to overtime in September.
Although Northwestern deserves credit for reaching the conference title game, it's hard to see Shea Patterson and Co. slipping up one step from the playoff after racking up over 30 points in five of the six games since the win over the Wildcats.
No. 2 Clemson vs. No. 3 Notre Dame
No. 2 Clemson continued its path of domination by holding its sixth opponent under 10 points Saturday in a 35-6 victory over Duke.
The Tigers should cruise to their 12th regular-season victory against South Carolina, but the Gamecocks enter with wins in three of their last four games and an eye on a high-profile bowl game with the SEC possibly putting three programs in New Year's Six contests.
If Clemson beats South Carolina, it has to be wary of the upset potential Pittsburgh carries in the ACC Championship.
The Panthers handed Clemson its only loss of the 2016 season in a November clash in Death Valley.
Although Pitt knows what it takes to knock off Dabo Swinney's team, there's a massive gap in talent between the two sides, and a Tigers defensive line chock full of NFL prospects should make sure the Tigers advance to the playoff.
Notre Dame shook off any doubts about its playoff resume by easily dealing with Syracuse at Yankee Stadium in Week 12.
All the Fighting Irish have to do in Week 13 is knock off a reeling USC side on the road to ensure themselves of a spot in the playoff.
Even if chaos ensues around them during conference championship weekend, the Irish should be safe as the No. 3 seed or better.
Brian Kelly's team has been locked into the No. 3 seed for quite some time, but if Alabama or Clemson fall, it could end up higher with a rematch against Michigan looking straight at it, or a clash with an SEC power like Georgia or Alabama in its future.
Follow Joe on Twitter, @JTansey90