The Live Chat is every Tuesday at noon. Read it in full at startribune.com/vikings.

Vikings beat writer Dan Wiederer does a Live Chat at noon on Tuesdays at startribune.com. Here is an edited version of this week's Chat.

Q Where's John Carlson? Also, do you think Jerome Simpson is going to be the answer in stretching the field?

A Carlson's invisibility -- zero catches, one target -- through two weeks is just plain odd given how hot the Vikings were in pursuit when free agency opened. You might think the knee injury he suffered in camp was still bothering him. But coach Leslie Frazier said Monday that's not the case. Regarding Simpson, his return will help. But he saw his last game action Aug. 24. Who knows how much rust he'll have to knock off when getting back into the flow in Week 4 at Detroit?

Q Why is everyone on Christian Ponder? His QB rating is off the charts. He looks good. We are just shooting ourselves in the foot the first two quarters and we need to dump that Cover 2.

A Ponder's been solid through two weeks and has done just about everything the Vikings are asking. Being safe with the football. Trying to avoid negative plays. We'll see if they can gradually help him expand what to do with the offense and the football. But so far, Ponder has been solid.

Q Seeing how athletic Everson Griffen looked on that big sack late in Sunday's game, how are they looking to get him more playing time?

A With the defensive line rotation that they've been using, Griffen has gotten a few more looks. Still, he's a guy they like to use as an inside rusher on passing downs. Which is exactly what he was doing on that 22-yard sack you just mentioned. The guy's a pretty good athlete. Needs a bit more discipline overall. Don't forget, he jumped offsides with 18 seconds left and gave the Colts their final 5 yards.

Q Is it possible to get Joe Webb in on a few downs early in the game to create some energy?

A I'm a little surprised that they haven't sneaked him out there even a little in the first two weeks. But it's clear that they're not attached to some of the gimmicks they used a year ago with him and they want to establish Ponder as much as possible.

Q Are the Vikings better suited to transition to a 3-4 defense? This seems to be the growing trend among NFL teams and could get Griffen more plays if he moved to the extra LB.

A They made all the personnel moves through free agency and the draft to fit the defense they run now, which has a lot of Cover 2 involved but aims to mix up zone and man coverages. Jared Allen has no interest in playing a 3-4 whatsoever. And at last check, he was their most established defensive star. The 3-4 can allow for more creativity and versatility in defensive calls to mix things up for the opposing QB. But you also need the guys who fit. And right now, that's not the way these Vikings were built.

Q Percy Harvin is really good but he can't do it all by himself!

A The Vikings absolutely need more WR help. In any way they can get it. Free agency, the draft. This past offseason they didn't want to spend big on some of the big name WRs (Vincent Jackson, Pierre Garcon) and they opted to address left tackle and safety in Rounds 1 and 2 of the draft. So what you're left with is Simpson (who has this year to prove he can be a long-term answer), Jarius Wright (who needs to stay healthy and give us a glimpse of what he's all about) and Greg Childs (career likely over after blowing both knees out at camp).

Q Why is Marcus Sherels still on the roster?

A Because he's sure-handed as a punt returner. Above all else, that's the reason. He also got some looks at CB when the Vikings went into dime D in Indy. But the hope was that Jarius Wright would eventually become a punt return weapon and yet he has consistent issues catching punts in practice.

Q Why was linebacker Audie Cole inactive?

A Seven players are inactive every week. It's a numbers game. Cole is not in position to play ahead of Tyrone McKenzie yet. And the Vikings use Larry Dean a lot on special teams.

Q No comment about Randy Moss' first regular season game ever against the Vikings?

A Moss is just a role player right now in SF. That said, it'll be interesting to see the reception he gets from Vikings fans. His 2010 exit was something.