While talking about the Vikings' recent success, Percy Harvin might have shed some light on what had him upset during the team's mandatory minicamp in June.

Remember the drama? Harvin went from saying he was unhappy, to requesting a trade to saying everything was fine.

Harvin was asked Monday if his role on the team was the issue last summer.

"It was just the identity of our offense," Harvin said. "Just not only me, just guys knowing exactly what the coaches are asking of them on a week-in and week-out basis. Not playing one position one week, and come in and not totally having a grasp on what they're asking for the next week."

Things apparently are better defined this season. Harvin is third in the NFL in receptions, first in yards after the catch (217) and continues to make his mark as a return man, getting his fifth career kickoff return for a touchdown in the Vikings' 20-13 victory over the Lions on Sunday.

Clearly, Harvin is happy with the way offensive coordinator Bill Musgrave is drawing up game plans.

"Coach Musgrave has done a great job ... of putting [tight end Kyle] Rudolph in great situations," Harvin said. "We have a package for [wideout Jerome] Simpson, which you've seen, where we'll take shots down field. So everybody, I think, knows their role, knows what coaches expect of them to do. Now you can just sit back and try to do it at the highest level you can."

D-line depth While defensive ends Brian Robison and Jared Allen didn't seem too enthusiastic about the idea of rotating players in and out of the defensive line this season, it appears that the Vikings have developed depth there.

Everson Griffen and Letroy Guion each had two sacks on Sunday.

Griffen, who plays both tackle and end depending on the situation, got one sack rushing from tackle and one at end, when he was in for Allen, who was working off a cramp. Guion, meanwhile, has clearly stepped up his game.

"Having the depth, having those guys inside, has helped us tremendously," Robison said. "It helps us out; me and Jared, we haven't had the greatest years so far. [Allen] has two sacks, I don't have any right now. It's one of those deals that they help us out and they kind of relieve the pressure off of us."

Griffen said he has benefited from concentrating on defensive line after coaches decided to quit trying to have him play some linebacker during training camp. He has three sacks in four games, one off his career high of four from last season.

"That's just me going out there and showing them what I can do every play," he said.

Rough stuff Chad Greenway had no issues with the personal foul penalty he drew Sunday when he delivered a jarring shot to Lions receiver Calvin Johnson over the middle. Greenway tried to pull up at the last second, but couldn't and was hit with a flag after his shoulder made contact with the defenseless Johnson's head.

In addition to the 15-yard penalty, a hefty fine is likely coming Greenway's way as well.

As for the Vikings' other personal foul penalty? Well, let's just say coach Leslie Frazier isn't ready to accept the referees' judgment that cornerback Josh Robinson was guilty of unnecessary roughness when he delivered a hard tackle on Nate Burleson after a 6-yard Detroit completion late in the first half.

Robinson actually body-slammed Burleson to the Ford Field turf.

"Seemed like a tackle -- just seemed like a tackle," Frazier said. "Now [it was] a hard tackle. But it is football. So we are going to get some clarification from the league. ... I have never seen anything written that we couldn't tackle a guy that way. So I am interested what the league has to say."

Etc. • Receiver Michael Jenkins suffered bruised ribs Sunday but should be OK.

• Linebacker Erin Henderson, who sat out the past two games, has still not been cleared to return to practice after suffering a concussion.