Jim Souhan: Jackson struggles, reminding us he's still a project

This was the kind of game that can send your average NFL defensive back in search of the comforts of recreational drugs.

The Vikings won their fifth consecutive game Monday night. They're probably bound for the playoffs. They overcame a lousy first half to beat the defending NFC champs.

They also raised as many questions as they answered, just like their quarterback.

For the second consecutive game, an average defense slowed Adrian Peterson. For the first time in the past four weeks, the Vikings allowed a mediocre opponent to put them on their heels.

And for the eighth time this season Tarvaris Jackson quarterbacked the Vikings to a victory without assuring us that he's ready to quarterback them into the playoffs.

Jackson is 8-2 as a starter this year, which is a little like saying Hank and Tommie Aaron combined to hit 768 home runs.

He threw for a career-high 249 yards Monday, including the catch-and-run to Bobby Wade that set up the winning score.

You like to call him T-Jack. It'd be better to call him Hi-Jack, or Lo-Jack, because Jackson doesn't do anything average.

The guy can look poised, or lost, sometimes on the same play. He can run over a linebacker or bail out on a game because of a leg cramp, as he did Monday night. He's too erratic to calm your worries and too successful to bench.

Maybe it was good the Bears were in town. They went to the Super Bowl last year with Rex Grossman, who now finds himself behind Kyle Orton and Brian Griese on the Bears' puddle-shallow depth chart.

Jackson threw three interceptions Monday -- one that wasn't his fault, and two that were ugly as all-purple uniforms. He botched a handoff to Adrian Peterson and made a handful of third-down throws that looked like Marko Jaric bounce passes.

And he won again, beating Orton, whose grooming habits make him look as if he's been in hiding with Jack Bauer, and whose throwing motion evokes images of tossing a bottlecap into a milk jug at the state fair.

He looked sharp enough early while everyone waited for the Vikings' running game to beat the Bears into submission so Jackson could enjoy his usual choice of easy throws.

When the Bears proved surprisingly stout against the run, Jackson was forced to throw downfield. The results were mixed.

When Jackson is sharp, he steps into his throws, showing a strong arm and textbook release. When he's rattled, he tends to stop moving his feet and toss the ball as if it were a dart and the receiver was the bull's-eye.

Perhaps never before had Jackson received this level of attention, and perhaps never before had he taken this many hard hits in the pocket. He displayed a willingness to stand tall and make throws under pressure; he also made killing mistakes, leaving him with six touchdowns and 10 interceptions on the season.

Four consecutive first-half Vikings drives ended similarly -- with lousy throws by Jackson, including one to a triple-covered Jeff Dugan and a throw-it-up-for-anyone interception that resumbled a bad punt.

"Obviously, I'm not happy with the way I played today," he said. "But we got the win. At the end of the day, Tarvaris, three interceptions; Vikings, win."

Jackson again showed that he's getting it, but how much more can he get before January begins?