No conference has stumbled quite like the Big Ten this college football season. Some of the trouble stems from factors the league could not control, but the results through the first half of the year have still fallen well short of what was expected.

Injuries have played a role. Ohio State has lived up to its billing but is now dealing with an injury to its starting quarterback. Oregon got off to a slow start, and the problem has deepened with Dante Moore sidelined for a month.

The timing is especially poor for the conference. The Big Ten had won three straight national titles with three different teams, and many had projected Oregon to become the fourth. Even the most committed SEC supporters had grudgingly conceded that their league had lost its grip on the sport.

Top contenders have struggled in all of the Power Four leagues so far this year, but the Big Ten stands apart in how far it has fallen short of expectations.

The betting numbers illustrate the point. Big Ten teams are 36-44-2 against the spread when favored this season, a .450 winning percentage that ranks second-worst among all conferences, just ahead of the American at .449. The cover rates are nearly identical, but the margins are not.

On average, Big Ten favorites are missing the spread by 1.82 points per game. The next worst league, the American, is missing by 0.44 points per game. The contrast is sharper given that favorites overall are covering 52.6% of the time by an average of 1.16 points. Favorites have generally thrived this season, just not in the Big Ten.

A handful of teams are largely responsible. The Big Ten had seven teams in the top 20 of the preseason AP Top 25. Ohio State has done its job, but the other six, Oregon, Indiana, USC, Michigan, Washington and Penn State, are a combined 8-28 against the spread as favorites. They are failing to cover by an average of 7.76 points per game, more than a touchdown.

That kind of underperformance makes it harder to assign power ratings to the conference's teams. In the latest ratings from CBS Sports writer Tom Fornelli, Texas Tech and BYU dropped out.