EDEN PRAIRIE, Minn. (AP) - For six years, Steve Hutchinson was the ornery, nasty, head-strong leader of the Vikings offensive line, a highly decorated veteran who grabbed hold of the unit from the moment he arrived in Minnesota and never let go.

The All-Pro left guard was in his third season here when the Vikings drafted an undersized, little-known center out of Notre Dame named John Sullivan, the 187th overall pick in 2008 who was just trying to prove he belonged.

Five years later, Hutchinson is gone and Sullivan has evolved from a question mark into the stabilizing force on a new-look unit. He has a new, long-term contract and an incredible amount of responsibility as the Vikings shuffle roles and bring in new faces to make life easier for quarterback Christian Ponder and the holes bigger for Adrian Peterson and Toby Gerhart.

It's nuts,'' Sullivan said on Wednesday after the team held an optional practice.I feel like it was just yesterday I was drafted at the end of the sixth round. But at the same time, we've had some ups, we've had some downs. It's time for some more ups.''

The Vikings are coming off a 3-13 season and their second straight last-place finish, the first time in the team's proud 50-year history that has happened.

One of the focal points of the offseason was improving the play up front, and the changes have been widespread. Hutchinson was allowed to leave and signed a free agent contract with Tennessee. Anthony Herrera, the guard on Hutchinson's right side for most of the last five seasons, was not retained either, and left tackle Charlie Johnson was moved to left guard to make room for first-round draft pick Matt Kalil.

With an open competition between Brandon Fusco, Geoff Schwartz and Chris DeGeare for the right guard spot, Sullivan and right tackle Phil Loadholt are the only players who remain in their positions going into training camp.

That puts a lot of the onus on Sullivan to keep the group together, spend extra time in the film room and make sure everyone gets on the same page as quickly as possible.

Playing the part of the vocal leader is nothing new on the field for Sullivan. That's what centers are required to do as they make calls at the line of scrimmage and adjust protection schemes to what they see from the defense. But being the guy who has to pull a guy to the side for some encouragement or admonishment in the locker room is a new role.

I had played center for a long time so in terms of on the field, I was comfortable from the start,'' said Sullivan, who took over for Matt Birk as the starting center in 2009.As a leader on a position group of this team, it's a little different. You try to just go out there, lead by example and only speak up when you need to.''

His guidance is already hitting home for Fusco, like Sullivan a sixth-round pick who came into training camp as a rookie last year a little on the doughy side. With help from Sullivan, Fusco has transformed his body, is much leaner and feels more prepared to step in going into his sophomore season.

He helps a lot, on and off the field,'' Fusco said of Sullivan.He's a great guy, a great mentor for me. Ever since I got here he took me under his wing. He's just taught me everything he's learned.''

Sullivan has also formed a fast friendship with Ponder, who is entering his first season as the unquestioned starter at quarterback.

The good thing about the relationship that we have is we're able to talk things through all the time,'' Ponder said.He's such a smart guy. He really understands the game and that's important for me and the center as well. So, getting on the same page on a lot of things and talking through things. Not only on the field, but when we're hanging out at the house we end up talking ball a lot. It's good.''

If the offensive line is going to improve the way the Vikings need it to this season, head coach Leslie Frazier is going to need to see a lot more of that from his man in the middle, who signed a five-year deal in December.

John is a guy we're really counting on,'' Frazier said.From a leadership standpoint, he was rewarded this past season with a good contract and because of how he has matured on the football field, he's really come along and he's begun to accept that role as a leader.''

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AP Sports Writer Dave Campbell contributed to this story.