With Harrison Smith out for today's game against the Falcons, the Vikings have confirmed that Antone Exum will start for Smith at free safety.

Exum, a second-year safety, made a couple of big plays in the preseason. But coach Mike Zimmer said that he needed to see consistency from Exum, which is why Robert Blanton and then Andrew Sendejo were the ones who started opposite Smith. Now with Smith out, Exum will get his shot today.

Rookie cornerback Trae Waynes is also out today against the Falcons, and as a result fellow corner Josh Robinson is active for the first time all season.

This is not an ideal week to be shorthanded in the secondary. The Falcons have the NFL's leading receiver in Julio Jones, who has 89 grabs for 1,189 yards so far this season. My guess is that the Vikings will ask Xavier Rhodes to shadow Jones while keeping a safety over top of him as much as they can.

There is some good news on the injury front, though. Defensive end Everson Griffen, the team's leading sack-getter, will start today. He was listed as questionable on Friday's injury report due to hip and shoulder injuries.

In addition to Smith and Waynes, quarterback Taylor Heinicke, linebacker Edmond Robinson, defensive end Justin Trattou, and offensive linemen Nick Easton and Jeremiah Sirles are also inactive today.

Inactive for the Falcons are running back Devonta Freeman, wide receiver Leonard Hankerson, cornerback Phillip Adams, offensive linemen James Stone and Bryce Harris, kicker Matt Bryant and defensive end Malliciah Goodman. Freeman, Hankerson and Smith were ruled out Friday.

Here is some pregame reading to keep you busy until the noon CDT kickoff:

— How good are the Vikings? We're going to find out in the next 18 days.

— The move to bring in speedster Mike Wallace has not been paying off.

— The offensive line has been up and down, but center Joe Berger has been a valuable insurance policy with starter John Sullivan lost for the season.

— Even with Smith out, I picked the Vikings to win by a touchdown today.