MINNEAPOLIS — If Brett Favre was the biggest reason for the Minnesota Vikings reaching the NFL's upper echelon last season, their success in recent drafts has to be right behind.

In the last four years, the Vikings have made 25 selections. Eleven have started at least 10 games, and six more have been occasional starters or become reliable role players. Eighteen remain on the roster.

For the Vikings, who lost to the champion New Orleans Saints in overtime of the NFC title game, to stay in Super Bowl contention they must sustain that success in this year's draft.

One of the rules of this uncapped season penalized the final four teams of the NFL playoffs — the Vikings, Saints, Colts and Jets — by requiring them to lose an unrestricted free agent before they could sign one.

That handcuffed the Vikings, who have been active in the free agent market since coach Brad Childress took over before the 2006 season. They lost versatile running back Chester Taylor to NFC North rival Chicago, and in their only run at a high-profile free agent to this point, lost LaDainian Tomlinson to the Jets.

"Knowing that you're not going to be a participant or you're on the sideline a little bit from the (unrestricted free agent) market, this emphasizes how important this draft is going to be," vice president of player personnel Rick Spielman said.

Cornerback Cedric Griffin is recovering from tearing a knee ligament in the NFC championship game that will likely still be mending when training camp opens. Linebacker E.J. Henderson is trying to return from a broken leg suffered in December. The team is also looking for depth behind veteran defensive tackle Pat Williams, running back Adrian Peterson and perhaps the 40-year-old Favre, who has yet to announce whether he'll return next season.

The Vikings are picking 30th in the first round Thursday night, but Spielman and director of college scouting Scott Studwell have put together a system that has been quite fruitful in all rounds recently.

"I feel like our guys will do a great job of evaluating like they always do; the scouts have done the same things they always do," Childress said. "Rick and Scott have got a great handle on that."

Just before Spielman arrived in 2006, the Vikings drafted linebacker Chad Greenway, Griffin, quarterback Tarvaris Jackson and defensive end Ray Edwards, all of whom have logged significant playing time. Greenway and Edwards had breakout seasons in 2009.

Spielman's first draft in 2007 brought Pro Bowlers Peterson and Sidney Rice as well as valued reserve defensive end Brian Robison. In 2008, the Vikings drafted a starting safety in the second round, though reviews of Tyrell Johnson's performance have been mixed, and future starting center John Sullivan in the sixth round.

Last year might have been the best draft yet for Childress, Spielman and Studwell, with Pro Bowler Percy Harvin in the first round and starting right tackle Phil Loadholt in the second. Third-round cornerback Asher Allen, fifth-round linebacker Jasper Brinkley and seventh-round safety Jamarca Sanford all started games in their rookie seasons, as well.

"We've been able to find some pretty good players in the later rounds that you may look back and say, 'Well, geez, how is John Sullivan a sixth-rounder?"' Spielman said. "Now if he's coming out in the draft this year, would you have drafted him earlier?

"I think there's value, and if you do a good job in your preparation and you do a good job in developing your board, then you can get some value for guys in those later rounds."

It's a cliche, but Childress said the key to success is staying true to the team's rankings and taking the best player available.

"Really you're just looking for a great player," Childress said. "I think we did a good job with that last year of taking some just good football players. A guy like a Jamarca Sanford. You say, 'Well, geez, you really didn't have a need for a safety.' That guy was a good football player."

Possibilities for their first pick this year include defensive backs Devin McCourty of Rutgers and Patrick Robinson of Florida State; defensive linemen Jared Odrick of Penn State and Brian Price of UCLA; and USC safety Taylor Mays.

Of course, if Notre Dame quarterback Jimmy Clausen falls to No. 30, as some mock drafts have projected, he could be hard to pass up. Spielman said he thinks this is one of the deeper drafts in recent memory, which certainly helps the Vikings at the bottom of the order.

"It bodes well for us," he said. "To pick 30, you wish you were picking 32, but to still be able to get quality players is a huge plus for us."