Jared Allen is playing in his ninth season in the NFL. He has been briefed on, and reminded of, the NFL's penchant for protecting quarterbacks. Whe he dove at Andrew Luck as Luck was running out of bounds, he gave a replacement official a chance to throw a flag, and the replacement official did.

The replacement official was, shockingly, right in this case.

Allen should have known better. He cost his team three points in a game that was decided by three points. The Vikings should expect more from one of their best, veteran players.

After the game, Allen told reporters, ``I guess you can't touch the quarterback."

That's a silly thing to say. No, Jared, you can't touch the quarterback. Not in the head. Not after the whistle. And not when the NFL"s future superstar is running directly out of bounds.

Football is an emotional game, but a veteran player should be able to control himself in key situations. Allen didn't.

Other reasons for the Vikings' loss:

-I've been covering the Cover-2 defense since Tony Dungy brought it to Minnesota in 1992. I've seen it work as designed. Yesterday, it broke down when Reggie Wayne went right down the middle of the field from the slot and caught a 30-yard touchdown pass from Luck.

In the Cover-2, the middle linebacker is responsible for taking a deep drop on passing plays and covering the middle of the field, which is left open because each safety takes responsibility for one side.

But no defense, not even the Cover-2, should ask a linebacker to cover a wide receiver, and certainly not an elite wide receiver. If you're going to play Cover-2, the safeties have to be aware of where the best receivers are.

The core philosophy of the Cover-2 is to force offenses to settle for short passes, allowing defenders to play the eyes of the quarterback. The Cover-2 exists as a defense against the big play. Ask a linebacker to cover an elite receiver, and you're defeating the purpose of the scheme.

-If the Vikings hadn't dumped Ryan Longwell for Blair Walsh, they'd be 0-2.

-I thought it was strange when the Vikings, in the midst of an offseason that was all about slowly rebuilding, signed John Carlson to a five-year, $25-million deal. The thing is, that would have been a silly contract even if Carlson had played well. As it is, Carlson has zero catches through two games.

Why, again, did the Vikings invest heavily in an injury-prone backup tight end?

-I'll be on 1500espn at 2:05 today. My Twitter handle is @Souhanstrib.