LANDOVER, MD. - Adrian Peterson had mixed feelings Sunday when he returned to FedEx Field. The Vikings running back severely injured his left knee there last Christmas Eve and had flashbacks to that career-altering moment.

"There was a little emotion," he said. "But I was able to overpower that with the main focus of trying to get out there and win."

Peterson, despite a tender left ankle, opened the day by rushing for 40 yards on the Vikings' opening field goal drive in a 38-26 loss to Washington. That included a shifty 32-yard run. Peterson also had a heated facemask-to-facemask argument with Redskins cornerback DeAngelo Hall in the first quarter.

"He slapped me in the face after making a good tackle," Peterson said. "And I was just telling him, 'Hey, don't do me like that, brother.' I looked him in the eyes and he knew I meant business."

Peterson finished with 17 carries for 79 yards and added a career-best seven catches for 50 yards. But his scoreless streak reached five games when his 1-yard touchdown run with 32 seconds left was negated by Kyle Rudolph's false start.

Peterson also expressed disappointment in himself, saying he missed some early opportunities to break free.

"I missed a couple [holes]," he said. "Should have been more aggressive. That's pretty much what it boils down to."

Destination: London The Vikings will play a home game at London's Wembley Stadium next season, a team spokesperson confirmed.

The official announcement will come Tuesday at the NFL's owners meetings in Chicago. The date and the Vikings' opponent for that 2013 game in England will also be announced then.

The Vikings also play could another game in London in 2014 or 2015 as their new downtown stadium is being built. That venue is scheduled to open in 2016 with the Vikings likely to play their 2015 home games and perhaps part of their 2014 slate at TCF Bank Stadium.

Still going strong Vikings receiver Percy Harvin recorded a career-high 11 catches in Sunday's loss. Harvin had 133 yards receiving and now through six games has 49 grabs for 540 yards.

Perhaps most impressive, Harvin continues to put up such gawdy statistics despite taking a beating almost every time he touches the ball.

Harvin appeared to be shaking off some leg soreness at various times Sunday but was never sidelined by the pain.

Padded stats Christian Ponder's 352 yards passing marked his second-highest output in 16 career starts. His career-best effort was a 381-yard day in Week 13 against Denver last season. But, just as happened in that loss to the Broncos, Ponder had three turnovers against Washington, including an interception returned for a touchdown.

That pick-six was delivered by former Viking Madieu Williams.

Ponder's numbers spiked dramatically in the fourth quarter as the Vikings tried to rally out of a 31-12 hole. After Williams' pick with 12:40 to play, Ponder went 20-for-28 for 199 yards with touchdown tosses to Michael Jenkins and Rudolph.

That had to hurt Sunday's biggest hit came courtesy of Redskins tight end Niles Paul, who absolutely blew up Vikings punt returner Marcus Sherels with 6:18 to play. Sherels caught Sav Rocca's 39-yard kick at his own 35 and was immediately blasted by Paul, his helmet and pink skull cap flying off his head.

Schwartz sighting Geoff Schwartz saw his first Vikings game action Sunday, subbing in at right guard for starter Brandon Fusco throughout the afternoon. Frazier noted that was a plan going into the game.

"We talked about it before the game and during the week," he said. "We wanted to be able to get some tape on Geoff in game situations. And this was an opportunity we thought we could get it done."

The Vikings signed Schwartz as a free agent in March. But the 26-year-old lineman who missed all of last season because of a hip injury suffered a sports hernia early in training camp and didn't play in the preseason

Etc. • Redskins rookie Robert Griffin III has six rushing touchdowns, a single-season franchise record for quarterbacks.

• Jenkins' six catches were a season high and his most since a nine-catch day against Detroit in Week 3 last season.

• The Redskins' victory was their first at home since a Week 2 defeat of Arizona in 2011. They had lost eight consecutive regular-season home games.

• The Vikings' inactives were Jerome Simpson, Marvin Mitchell, Brandon Burton, Mistral Raymond, Jarius Wright, Mark Asper and McLeod Bethel-Thompson.