GREEN BAY, Wis. — Maybe the Minnesota Vikings should have flirted more convincingly with Brett Favre.

Turns out they could have used him more than even the Green Bay Packers.

Whether you believe the Vikings tried to lure Favre to Minnesota this summer, or that Favre and Brad Childress just love swapping stories about the Wisconsin Dells, this is certain: Vikings quarterback Tarvaris Jackson did little Monday to dispel the notion that his team requires much more from the position, whether that improvement is to come from Jackson or a replacement.

With Jackson failing to capitalize on another 100-yard rushing game from Adrian Peterson, the new-and-promising 2008 Vikings looked a lot like the not-quite-good-enough 2007 Vikings.

And in the first half, Jackson and his team looked a lot like the aimless bumblers of 2006.

Jackson should be better than this. His teammates gave impassioned testimonials about his improvement. His coach pinned his reputation on his drafting and development.

Then, in one of the most highly anticipated season openers in Vikings history, Jackson amassed 16 — count 'em, 16 — yards passing in the first half. "Is that, like, a record?" Childress said, tongue in cheek.

Jackson went 2-for-7 in the first half, looking remarkably like the rookie who floundered in his first NFL start two years ago in Lambeau, when he completed 10 of 20 passes for 50 yards, was sacked three times and threw an interception in a 9-7 loss.

Monday, Jackson completed 16 of 35 passes for 178 yards, a touchdown and that final wild pitch of an interception. "That last turnover was the key," Jackson said of his pass that sailed way over tight end Visanthe Shiancoe's head. "I was just looking at Shank ... I just threw it too high. I've got to check my mechanics on film."

Jackson's work ethic is unquestioned. He's got a strong arm. He can and will run effectively. But the measure of an NFL quarterback is in split-second decisions and a mastery of the offense and a feel for the game, and Jackson sometimes makes inexplicably ugly throws.

You can argue that he missed the last two preseason games, that he's gotten precious few preseason snaps the past two seasons, that he's still a work in progress.

And Jackson did play better in the third quarter, immediately leading the Vikings 77 yards to a field goal, running 19 yards for a first down on third-and-7, then completing two passes for 47 yards.

This was according to the Vikings' plan, the plan that sounded so simple all summer. With a dynamic running game, all Jackson would have to do is beat defenses preoccupied with Peterson. All he would have to do is loft the ball to speedster Bernard Berrian, who had to be worlds better than Troy Williamson, and Viking fans would have to worry only about whether their sensitive skin could withstand two trips to Tampa this season — one in the regular season, one for the Super Bowl.

Monday, Jackson wasn't good enough, and neither were his receivers. Berrian, perhaps still bothered by his sore toe, had trouble getting past venerable Packers cornerback Al Harris. And if he can't get open deep, the Vikings become a horizontal passing team that can't back the safeties away from the line of scrimmage, making the going tough for Peterson.

Jackson rallied the offense in the second half, but that last, ugly interception decided the game and led to Jackson throwing his helmet in disgust.

"I've been a lot madder before," he said. "I just felt like if I didn't throw that interception, we were going to win that game.

"It was just too wide open for me to miss that pass."

Favre proved many times in Lambeau that a clutch fourth-quarter drive can save a game, a season, even a quarterback's reputation.

Instead, Jackson, with that last wild pitch, revived every question we've ever asked about him.