LAKE FOREST, Ill. -- Lance Briggs didn't hesitate when asked to give his MVP pick for the 2012 NFL season.

“Adrian Peterson," Briggs said.

The choice is tough to argue. Peterson stunned the NFL world when he returned for the Minnesota Vikings' regular season opener against the Jacksonville Jaguars, roughly eight months after he suffered a devastating knee injury at the end of 2011.

To say Peterson picked up where he left off might be an understatement.

Not only does the four-time Pro Bowler lead the NFL with 1,446 rushing yards, Peterson has gone over 100 yards on the ground in six straight games, including a monster effort last week against the Green Bay Packers when he ran for 210 yards on 21 carries.

"He's running stronger since he's come back from his injury than last year," Briggs said. "The guy is a very tough guy to bring down. He's a full head of steam, and once he gets tackled, it looks like he's looking for the next time to get the ball. 'I want the ball again and again, again, again.' He's pretty relentless, which is great for defensive players. Great players will always raise your level of play."

Two weeks ago the Bears held Peterson to 108 yards, his lowest rushing output in his current six-game streak. But the Vikings only gave Peterson the ball 18 times in the Bears' 28-10 victory, a number that is expected to go up when the teams rematch Sunday at the Metrodome.

Of course, the Bears are familiar with Peterson's explosive ability. As a rookie in 2007, he ran for 224 yards and three touchdowns in a 34-31 Minnesota victory at Soldier Field. Peterson set the single-game NFL record with 296 rushing yards that same season against the San Diego Chargers.

"He's running crazy," Bears new middle linebacker Nick Roach said. "It's fun to watch him run, but at the same time, it's a great challenge for us to be able to go and try to stop that. He does everything. He runs over guys, runs around them, makes them miss. His effort is extremely high. To have a chance to stop him, you just have to match it with everybody."