SEATTLE — Twelve minutes away from becoming relevant in a rebuilding season, the Seattle Seahawks reverted to their losing ways.

Now any thoughts the Seahawks might have held about getting back into the fringes of the NFC playoff picture are likely gone after a fourth-quarter meltdown.

“I don’t know what we’ve got to do better,” Seattle QB Tarvaris Jackson said. “I feel like we had the game, all we had to do was finish it and we didn’t finish it.”

Washington QB Rex Grossman hit Anthony Armstrong on a 50-yard touchdown midway through the fourth quarter and the Redskins went on to stun the Seahawks 23-17 on Sunday.

Seattle led 17-7 early in the fourth quarter, then watched the lead whittled away in a hurry by Grossman, who was brilliant early, shaky in the middle and then great again in the closing minutes.

Washington (4-7) snapped its six-game losing streak, its longest since dropping the first seven games of the 1998 season.

And while Grossman was making throws, the Seahawks offense disappeared in the closing minutes. The quarter actually started well for Seattle with Jackson finding Golden Tate on a 15-yard TD pass with 12:45 left to give Seattle its 10-point advantage.

Nothing good happened for Seattle from there.

Seattle ran 13 offensive plays on its final four possessions. No play went for more than 11 yards and Seattle (4-7) failed to pick up any first downs.

Along with the offensive struggles, the defense was hurt by the Redskins for big plays.

Roy Helu ran for a 28-yard touchdown by hurdling Seattle defensive back Roy Lewis and breaking the tackle of Kam Chancellor. Brandon Browner was beat again on Grossman’s deep touchdown throw to Armstrong that came on third-and-19 and following an intentional grounding call.

“We just didn’t finish the game,” running back Leon Washington said. “You have to play four quarters and when you commit a lot of penalties, don’t make plays when you have to, that’s what happens.”

The Seahawks racked up nine more penalties and were forced to take two timeouts due to substitution problems that continue to plague the team. The Seahawks have had eight or more penalties in nine of their 11 games this season.

“The things that we have chosen to do to make the points haven’t hit home,” coach Pete Carroll said. “That’s what I told them. I’m not getting it done.”

“If the same guys keep making mistakes, you have to put other guys in. We’ll have to look at that.”

Carroll has made a point the past two weeks to point out every penalty racked up in the team’s Monday meetings. It’s been a lengthy list with Seattle picking up 13 penalties in each of the previous two games, but the message doesn’t appear to be getting through to his players.

“It just comes back to discipline. We’ve just got to be more disciplined,” Chancellor said. “We got to start at practice. We get penalties in practice and it shows in the game. So we just got to start at practice and be penalty-free in practice so it can carry over to the game.”

Jackson was 14 of 30 for 144 yards and was intercepted in the final minute by DeAngelo Hall. The late rally by Washington to snap its longest skid since 1998 ruined another stellar day from Marshawn Lynch, who rushed for 111 yards and caught a 20-yard touchdown pass in the second quarter.

But Lynch and his teammates were left watching the Seahawks miss a chance for their first three-game win streak under Carroll. Now comes a quick turnaround and a game on Thursday night against Philadelphia.

“You had an opportunity to take another step and I feel like we let it slip today,” said Seattle DE Red Bryant, who had a blocked field goal and extra point. “That’s just a sign of a young team in terms of you have to take advantage of your opportunities.”

Grossman threw a 2-yard touchdown pass to Fred Davis as part of Washington’s nearly perfect first quarter, threw a pair of interceptions in the second and third quarters, then led two touchdown drives in the fourth after Seattle took a 10-point lead. He finished 26 of 35 for 314 yards and was 7 of 9 passing in the fourth quarter.

“We have a great bunch of guys, our locker room has a lot of character and a lot of team chemistry, a lot of good people, hard worker, tough great football players that believe in one another, and after a losing streak like this we stepped up and made plays that we needed to make,” Grossman said. “It’s a tough place to play out here in Seattle, it’s very loud, it’s been a long trip. (It’s) pretty rewarding to win especially the way we did.”

Washington also got a spark from Helu, who had the first 100-yard game of his career, running for 108 yards on 23 carries and a memorable first NFL touchdown run.

“That was one of the most impressive runs I’d ever seen, to be able to hurdle somebody and keep moving, it was awesome,” Grossman said. “That was the play that really got us going there in the fourth quarter and got us the win.”

Notes: Washington FB Darrel Young and Seattle WR Sidney Rice both left with concussions and did not return. ... Seattle starting WRs Rice and Mike Williams were held without a reception. ... Washington’s 172 yards of offense in the first quarter were its most in a first quarter since 1999 against Philadelphia.