Adrian Peterson rushed for 31 yards on 19 carries in the Vikings season opener at Tennessee. He closed out last season with just 45 yards on 23 carries in the first-round playoff loss to Seattle.

Rewind to Week 10 of the 2015 season and Peterson's rushing totals have consistently been down. Over his last nine games, Peterson is averaging 66.7 yards per game and 3.4 yards per carry. His career averages are 96.7 yards per game and 4.9 per carry. By Peterson's standards, he is in a little bit of a slump.

Let's start by noting the obvious: Peterson is one of the best running backs in the league and opposing gameplans will always be centered on stopping him. But because Peterson is one of the best, he often finds a way to ruin their plans.

The 31-year-old rushed for 1,530 yards and 11 touchdowns last season to win his third rushing title, earn his fifth First-Team All-Pro honor, and played in his seventh Pro Bowl. He walked out of the Georgia Dome on Nov. 29, 2015, having just dominated the Atlanta Falcons with 158 rushing yards and two touchdowns on 29 carries. Two weeks earlier against Oakland he rushed for a season-high 203 yards and one touchdown.

But his stats haven't been the same since.

Peterson hasn't hit his career averages since that Sunday in Atlanta seven games ago (including the playoff loss to Seattle). Since the Falcons game – in which he also had two catches, for 31 touches – he's topped 70 yards just once: 104 yards on 22 carries against the Giants last December, his one 100-yard effort since Atlanta.

A week after his big day against the Falcons, Peterson was held to just 18 yards on seven carries in a 38-7 loss to Seattle and his impact was limited the rest of the season.

The trend seems to have followed Peterson into the new season, but it's not uncommon for him to start slow. He hasn't rushed for more than 100 yards in a season opener since 2009, and since he began sitting out of preseason games his numbers continue to decline in Week 1.

Peterson hasn't run the ball in the preseason since 2011 and has opened the last two regular seasons with just 31 yards in each game.

However, history shows Peterson responds well in Week 2. Since 2010, Peterson has rushed north of 100 yards four times in Week 2 (in 2014 he was suspended after Week 1). Last season, he put together back-to-back 100-plus-yard efforts in Week 2 and 3 to jumpstart another historic year.

Peterson said he believes he can play until he's 40. If his body can back up his words, the Vikings home opener at U.S. Bank Stadium would be the obvious opportunity to break this slump and prove he still has plenty left in his legs.