The Vikings announced running back Adrian Peterson had groin surgery Thursday and is "expected to make a full recovery in approximately six weeks."

But then what?

This makes three offseason surgeries in three consecutive years for a workhorse NFL running back with 2,354 career touches and a 29th birthday that will arrive on March 21.

Yes, the 2012 NFL MVP is barreling toward Canton, Ohio, and the Pro Football Hall of Fame. But have Peterson and the Vikings reached a point at which the pedal that regulates Peterson's career pace can't — or, better yet, shouldn't — always be pinned to the metal?

Peterson missed two games and had just 18 carries in the team's final four games. Yet his 279 carries were 235 more than the team's next-highest total of 44, which belonged to No. 3 running back Matt Asiata.

That 235-carry disparity was the second largest in the league. Only Philadelphia's LeSean McCoy, the league rushing champion who played in all 16 games, owned a larger difference. His 314 carries were 239 more than teammate Bryce Brown's total.

Peterson's seven-year, $96 million contract runs through 2017.

The Vikings head into free agency likely to lose little-used backup Toby Gerhart when they might need him most. Gerhart, who has just 276 career carries in four seasons, will no doubt be looking for a starting job outside of Peterson's considerable shadow. The Vikings will be left with Asiata, Joe Banyard and obvious interest in the backup running back market.

New Vikings offensive coordinator Norv Turner might be the coach to get optimal production out of Peterson without overdoing it. That's going to be especially important, with Peterson still under contract for four more seasons and due to make $12 million in 2014.

In 2006, the year before Turner became head coach in San Diego, Chargers future Hall of Fame running back LaDainian Tomlinson had 348 carries — the second-highest total of his career — while leading the league in rushing with 1,815 yards. In 2008, the year Tomlinson turned 29 before the season, he had 292 carries for 1,110 yards and 11 touchdowns.

Of course, it was easier for Turner to pull back on Tomlinson when he had a quarterback, Philip Rivers, who was leading the league in touchdown passes (34), yards per attempt (8.4) and passer rating (105.5).

The only time the Vikings have had exceptional quarterback play in Peterson's seven seasons was 2009 with Brett Favre. That year, Favre set career highs in completion percentage (68.4) and passer rating (107.2) while Peterson carried the ball 314 times, his lowest total of any season in which he's played every game.

Peterson already had pulled out of the Pro Bowl when the Vikings announced the surgery Thursday. In a statement, the Vikings said Dr. William Meyers was "able to successfully repair Adrian's abductor muscle while also doing a compartmental release" at the Vincera Institute in Philadelphia.

Meyers also performed the sports hernia surgery on Peterson last offseason. The year before, Peterson had surgery to repair the anterior cruciate and medial collateral ligaments in his left knee.

Peterson came back from the knee reconstruction in nine months and was able to rush for 2,097 yards — the second-highest total in NFL history — while winning league MVP honors.

This past season, however, Peterson lost the rushing title while battling problems with the groin during the second half of the season. He missed two of the Vikings' final three games because of groin and foot injuries.

The groin also clearly affected him earlier in the second half of the season, particularly on Nov. 17 at Seattle, when he rushed for only 65 yards on 21 carries (3.1) in a 41-20 loss to the Seahawks.

Peterson, however, still managed to finish with 1,266 yards and 10 touchdowns in 14 games. And even as he battled the groin injury, Peterson still had a combined 67 carries for 357 yards in back-to-back overtime games against the Packers and Bears in late November and early December.