Adrian Peterson's wife gives birth to boy on Sunday morning

Rick Spielman: 'Adrian Peterson is a key part of our football team' (0:27)

Minnesota Vikings' general manager Rick Spielman says on NFL Insiders that the team is positively reacting to RB Adrian Peterson's return, and despite missing the preseason, he sets the tone both offensively and defensively. (0:27)

MINNEAPOLIS -- Adrian Peterson is active for the Minnesota Vikings' game against the San Diego Chargers after his wife, Ashley, gave birth to the couple's second child Sunday morning.

The Vikings announced Ashley Peterson gave birth to a boy named Axyl Eugene Peterson on Sunday morning, and Adrian Peterson joined his teammates on the field during warm-ups about 75 minutes before the game.

Ashley Peterson told ESPN in June that the boy would be Adrian Peterson's sixth child. The couple also has a 4-year-old son together.

The last time the Chargers came to Minneapolis, Adrian Peterson broke the NFL's single-game rushing record with 296 yards in 2007.

On Sunday -- in Peterson's third game back after last year's suspension -- he could be in line for another big day. According to ESPN Stats and Information, the Chargers have allowed 3.87 yards per carry before contact this season. That's the most in the NFL by more than half a yard. And in 11 games since the start of 2012 in which Peterson has had that much room to run, he's put up impressive numbers.

Peterson has averaged 158.3 yards per game when he's averaged at least 3 yards before contact, according to ESPN Stats and Information. He has run for 170 yards or more six times in those games, and has surpassed 200 yards three times.