Depth welcomed in secondary by Frazier

Vikings coach Leslie Frazier was talking about the sheer joy of having depth in the secondary for the first time since 2009 when he was asked just how agonizing it must have been to game-plan for NFC North teams and the other high-powered offenses the Vikings faced during last season's 3-13 nightmare.

"Don't take me back!" said Frazier, extending his arm before the question had ended. "Those are bad memories, man."

Then, Les being Les, he politely expanded on the answer in a way that better illustrated the frustration that he and his coaches felt when their secondary collapsed because of injuries and cornerback Chris Cook's legal issues.

"When you know going into the game that you're limited and you know that other people look at the tape and know you're limited, it's tough," he said. "We played a team -- I won't mention the team -- and one of those guys who coaches the secondary called me after the game and said, 'Man, going into the game, we knew if we put this package on the field, you couldn't match up. And if we did this, you couldn't match up. I don't know what you're going to do, but you guys have to address your secondary.'"

The Vikings did just that. They signed veterans Chris Carr and Zack Bowman in free agency. They drafted three defensive backs, including starting free safety Harrison Smith in the first round. And they also benefit from the return of Cook and Antoine Winfield, who missed 11 games because of a neck injury and a broken clavicle.

Frazier said injuries and a lack of depth have kept the Vikings from using man coverages on a consistent basis since 2009. Inconsistent safety play didn't help either, Frazier said.

"Especially today, when you rely on safeties to cover tight ends," Frazier said. "You know when you have a liability there, it's going to get exposed when you play man. So you're less likely to play man."

Blanton could see his first preseason game action Friday against the Chargers. A decision on his availability has not yet been made. Yet after missing significant practice time the past month, he must not try too hard to make up for lost time.

"Coming back from a hamstring, it's one of those injuries where you think you might be ready and then sometimes it will tug a little bit," Frazier said.

Another rookie defensive back under the spotlight Friday will be cornerback Josh Robinson, whose development seems to be coming quickly through the preseason. Robinson drew praise once again for his burst and recovery speed during last week's preseason win over Buffalo. And with Cook (concussion) sitting out Friday, Robinson should get a more extensive look with the first-team defense in nickel packages.

"I feel like I've made strides in cleaning up my technique and paying attention to doing all the little things right," he said. "I'm really focused on making sure not to make mental errors."

Etc.• Nose tackle Letroy Guion will not play against San Diego after aggravating a right knee injury on Tuesday. Guion suffered a posterior cruciate ligament sprain in the knee during the Vikings' preseason opener in San Francisco. He did not participate in Wednesday's practice, watching from the sideline with his right knee wrapped up. Guion did have an MRI on the knee, but no structural damage was found.