Defense has allowed eight second-half plays of 25 yards or more

It's difficult to saddle the Vikings' defense with too much blame for blown first-half leads of 10, 17 and 20 points during this most bizarre of 0-3 starts.

For starters, the time of possession in the second half is about 57 minutes for the opposing offense and 33 minutes for the Vikings' offense. That's a ridiculous amout of time for any defense to be left on the field, especially against three good quarterbacks in Philip Rivers, Josh Freeman and Matthew Stafford.

The offense is 1-for-15 on third downs, 0-for-1 on fourth down and has two field goals in 16 second-half possessions. So I'll put the brunt of the blame on that side of the ball.

Also, how does a team built around Adrian Peterson only run the ball seven times for 8 yards in the second half? Peterson had five carries for 5 yards. The Lions were down 20 points and have absolutely no running game to speak of. Yet they ran the ball 13 times in the second half for 10 yards.

However ...

One can't overlook two things when it comes to the Vikings' defensive performances in the second half: Big plays plays and penalties.

The Vikings have allowed eight plays of 25 yards or more in the second half. They've also had eight defensive penalties accepted for 70 yards of punishment.

San Diego: 37-yard screen pass leads to touchdown four plays later.

Tampa Bay: 27-yard touchdown run; 51-yard screen pass leads to field goal three plays later; 25-yard touchdown pass.

Detroit: 32-yard touchdown pass, 27-yard pass leads to field goal three plays later, 60-yard screen pass leads to touchdown one play later, 40-yard pass in overtime leads to game-winning field goal on the next play.

Here are the penalties broken down:

San Diego: Unnecessary roughness on Cedric Griffin leads to game-winning touchdown five plays later; Chargers then run out the clock with the help of three offsides penalties on Letroy Guion (two) and Fred Evans.