When the intensity has picked up for the offense on the other side, Minnesota's defense has been glaringly vulnerable to giving up scores.
The Vikings were at their worst during the two-minute drills by Indianapolis and rookie quarterback Andrew Luck in Sunday's 23-20 loss. The Colts drove for a touchdown with 7 seconds left in the first half to stretch their lead and then won a field goal with 8 seconds remaining in the game.
The loss dropped the Vikings to 1-1 as they prepare to host the unbeaten 49ers this Sunday, the first of a two-game road swing that also will take San Francisco to New York to play the Jets.
Though quarterback Christian Ponder and rookie kicker Blair Walsh saved Minnesota with a late surge to beat Jacksonville in overtime in the opener, the Vikings let the Jaguars move 76 yards in six plays and less than a minute to take the lead with 20 seconds remaining in regulation.
"We got into this last year: `Well, we did this good and that good. We didn't finish, but we had a really good first half.' Well, you're losing, so it doesn't really matter," linebacker Chad Greenway said. "At the end of the year, you're 3-13 and all you have is a bunch of excuses. We're not trying to do that again this year. We're really not."
The Vikings were stingy at times, but when they really needed to stiffen they wilted. After tying the game with 31 seconds left on a touchdown pass by Ponder, who leads the league in completion percentage at 75.8, they let Luck move the Colts 45 yards in three plays and 19 seconds to get just close enough for the go-ahead 53-yard kick.
"We've got to do better," coach Leslie Frazier said. "The way our team is built, we're going to play a lot of close games."
Just as inexcusable and costly was the drive by the Colts at the end of the first half, when Luck found a wide-open Reggie Wayne in the middle of the zone coverage for a 30-yard touchdown on third-and-3 to cap an eight-play, 64-yard sprint in 64 seconds. That stretched the lead to 17-6.
Safeties Harrison Smith and Mistral Raymond were late to converge on Wayne, but middle linebacker Erin Henderson was assigned to follow Wayne up the seam. Frazier said the coaches were confident enough in Henderson's ability to track the veteran wide receiver they weren't worried about a mismatch in speed. Henderson said he was deep enough but simply misjudged the ball as it traveled through the air.
"That was my biggest fear going into the game, that we would play decent football, we would play good football, and they would sneak in a couple big plays on us, and we would be in a dogfight," Henderson said, adding with bravado about his mistake: "Hopefully there are quarterbacks out there watching it, and they think that they can come in and try to get some on me, too, and I've got a little surprise for them if they want to present that to me."
The Vikings are 27th in the league in third-down conversion prevention. They let the Colts move the chains seven out of 16 times in those situations, none more egregious than on their 14-play possession that ate up more than half of the third quarter. Thirty of the 53 yards gained were by penalties.
After Andrew Sendejo's roughing-the-kicker call on a punt at the Indianapolis 45 extended the drive, Allen chased Luck out of bounds on third-and-16 at the Minnesota 46 and tackled him by the ankles well across the line. The yellow flag flew, and the Colts kept moving for another field goal to push their edge to 14 points.
Allen sharply criticized the call, but it appeared obvious, whether replacement or regular referees were working.
"Got to have a little awareness of where you are on the field. It looks like he kind of lost where he was on the field," Frazier said.
The Vikings were penalized 11 times for 105 yards. They also had an encroachment infraction during a touchdown drive in the first quarter, an offside penalty while the Colts were on their way to a field goal in the second quarter and another offside penalty before they set up for the winning kick in the fourth quarter.
"We have to be more disciplined. It's not really a mystery," Greenway said.
Up next: Vikings doomed by defensive lapses
Niners Digest Top Stories
Week 2: Fantasy Football Deep SleepersFantasy Football Expert Jack Delaney reveals some under-the-radar players that could help you gain an edge in your Week 2 matchup.
2016 Expert Sleepers, Busts & BreakoutsThe best high-stakes Fantasy Football Experts and world's highest-ranked fantasy players have contributed to what we call Preseason Pro. A collection of hand-picked fantasy…
Top 10 NFL Celebration FailsRevisiting some of the worst celebration fails in NFL history.
Scout NFL Network08/24/2016
10 greatest one-handed catches in NFL historyCheck out the most jaw-dropping, awe-inspiring one-handed catches of all-time in the NFL. Find out who comes in after Odell Beckham's catch against the Dallas Cowboys.