INDIANAPOLIS -- The Vikings were either first or second in the NFL against the run from 2006 through 2009, largely because of the play of their defensive line.

But in 2010 the Vikings gave up 102.2 yards per game and were ninth versus the run. That did not sit well with Leslie Frazier, who took over as the Vikings defensive coordinator in 2007 and was named coach with six games left in the 2010 season.

Frazier made it clear that drop won't be tolerated either, telling reporters at the NFL Scouting Combine on Friday that, "we are going to try to upgrade our defensive line." Frazier doesn't know if that will be accomplished through the draft or free agency.

"That's a scenario where we want to do some things that can really help our defensive line," Frazier said. "We're aging at one of the spots, we need to do some things to improve. One of the mantras has been being good against the run, stopping the run. We've kind of slipped a little bit so we have to take a look at some things and see what we have to do to improve in that area."

Frazier is right in that the Vikings aren't young when it comes to the starting members of their line. Nose tackle Pat Williams is 38, defensive tackle Kevin Williams is 30 and defensive end Jared Allen will turn 29 in late April.

Pat Williams will be a free agent -- whenever that period begins -- and likely will not return. Starting left end Ray Edwards also could become a free agent depending on what happens with the CBA, as could Brian Robison. The good news for the Vikings in all of this is that the defensive line class for this draft is considered to be extremely deep.

"We need to just look at the fact that we are getting a little bit older," Frazier said. "So we've got some depth on the line. We still have Fred Evans, although he's a free agent. We stil have Letroy [Guion], who we think has a chance. We've still got Jimmy Kennedy, who is on the roster as well. So we've got to get some young guys going. Some day Pat is going to retire and somebody's got to be able to step into that role. He's been a great, great player for us for a number of years. But we need a young guy to step up and we've got to determine whether that's Letroy or whether that's Fred or whether we've got to draft someone."