Back in the day, it used to be a major occurrence when a Football Championship Series team (D1-AA) defeated a Football Bowl System (D1) team. In today's college football world it is common for multiple FCS squads to pull off this upset...each week.

Today, the stunning FCS upset is not against an FBS team, but against a ranked Power Five team (ACC, Big 12, Big Ten, PAC-12 and SEC). Between 1978 and 2006, the FCS schools defeated a ranked Power Five teams once. In 1983, Cincinnati (a D1-AA team at the time) defeated No. 20 Penn State 14-3 in Happy Valley. This was the first time an FCS team took down a ranked Power Five opponent. 

After Cincinnati's upset, it took 24 years for another FCS team to do the unthinkable against a ranked P5 team. Yes, the Appalachian State monumental upset of No. 5 Michigan was only the second time in history an FCS squad defeated a ranked P5 program. Between 2000 and today, five more FCS teams defeated ranked P5 squads.

The six FCS wins over ranked P5 opponents:

• 1983 // Cincinnati 14, No. 20 Penn State 3
• 2007 // Appalachian State 34, No. 5 Michigan 32
• 2010 // James Madison 21, No. 13 Virginia Tech 16
• 2013 // Eastern Washington 49. No. 25 Oregon State 46
• 2015 // Citadel 23, No. 25 South Carolina 22
• 2016 // North Dakota State 23, No. 13 Iowa 21

As you can see above, the FCS has taken down a ranked Power Five school three out of the last four seasons. Will it happen this year? The trend says yes. Now the question is, will it happen this week? Teams on major FCS upset alert are No. 7 Washington, No. 12 LSU, No. 18 Virginia Tech, No. 22 Florida and No. 25 Tennessee.

It's not just the ranked Power Five teams that should be on notice. In fact, it is the unranked P5 teams that are getting taken down on a more frequent basis. Since 2010, just over seven seasons,  FCS caliber schools have won 23 games against the mighty Power Five. that is an average of 3.7 games per season. Between 1978 and 2009 (32 seasons) the FCS won 39 games (1.2 games per year).

The last time an FCS level school did not beat an FBS opponent? 2008.

Which FCS team will defeat a Power Five opponent this week?

Montana at No. 7 Washington

Why Montana Will Win

The Grizzlies have defeated seven FBS level teams and own a .241 winning percentage. Montana has defeated Oregon State twice (1990 and 1996). The last time the Grizzlies defeated a team in the FBS was 2003, so they are due.

Why Montana Will Not Win

Washington has never lost to a team from the FCS and had its wake-up call against Rutgers last week.

Chatanooga at No. 12 LSU

Why Chatanooga Will Win

Chatanooga has defeated three FBS opponents. The last being a 42-14 thrashing of Georgia State in 2013. The Mocs are also hoping that LSU is overlooking them for next week's SEC season opener against Mississippi State.

Why Chatanooga Will Lose
The Mocs have never defeated a ranked Power Five team and LSU has never lost to a team from the FCS.

Delaware at No. 18 Virginia Tech

Why Delaware Will Win

The Blue Hens have an impressive 8-8 (.500) record against FBS teams and Virginia Tech is coming off an emotional win against West Virginia. Delaware's last win over an FBS team was against Navy (59-52) in 2007.

Why Delaware Will Lose

Delaware has never defeated a Power Five team, not to mention a ranked P5 team.

Indiana State at No. 25 Tennessee

Why Indiana State Will Win

The Sycamores have won an impressive nine games against FBS squads and Tennessee travels to No. 22 Florida next week. ISU's last victory was against Ball State (27-20) in 2014.

Why Indiana State Will Lose

The team known more for Larry Bird has lost 55 out of 64 games against FBS opponents and has never defeated a ranked FBS team.

Which FCS team has the best shot at beating its ranked opponent?

ICYMI
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Know Thy Enemy: Comparing Oklahoma's and Ohio State's Offensive Recruits
Know Thy Enemy: Comparing Oklahoma's and Ohio State's Defensive Recruits