The Sounders are now 14-5-6 with 48 points, one ahead of Portland (13-5-8, 47 points) in the USL First Division standings. Seattle got some help from Puerto Rico on Sunday as the Islanders blanked the Timbers in San Juan, 1-0.

The victory extended the Sounders’ ever-growing unbeaten streak. Seattle now has gone 12 straight games in league play (10-0-2) and 15 in a row overall (13-0-2) without a loss. The Sounders, with three regular-season games left, also have a game at hand on Portland in their bid to secure the first-place position.

Seattle, which plays host to Minnesota on Friday night at 7:30, already has secured a playoff spot after missing the postseason in 2006.

Charleston, still trying to get into the playoffs, fell to 8-13-5 with 29 points. The Battery lost all three games on its West Coast road trip to Portland, Vancouver and Seattle by 1-0 scores.

LeToux was the last of three players to get his foot on the ball as the Sounders got onto the board late in the first half.

Roger Levesque, coming down the middle of the field, laid the ball off toward Hugo Alcaraz-Cuellar on the right wing. Alcaraz-Cuellar sent a low crossing ball into the box. It went behind Levesque and right to the foot of LeToux, positioned eight yards straight in front of the net. LeToux’ shot went untouched into the back left corner, as Battery goalkeeper Keith Wiggans never came close to getting his hands on it.

Seattle kept the pressure on a tired Charleston team throughout the game. The Battery, playing their second game in less than 24 hours (they lost at Vancouver on Saturday) were outshot for the game, 19-9. It was 10-5 for the Sounders during the first half and 9-4 in the second.

Twice just before halftime, the Sounders were inches away from making it 2-0. A Levesque header from the top of the six-yard box went just wide in the 45th minute. Then during stoppage time, a header by Levesque bounced off the right post right to the feet of Sounders defender Taylor Graham. But before he could wind up and shoot, the ball was cleared out of danger.

Charleston, was not without its opportunities. Kenny Uzolgwe ripped a shot from the top of the arc that was saved by Sounders goalkeeper Chris Eylander in the 17th minute.

Just half a minute later, Gordon Chin, shooting from just outside the penalty area on the right wing side, drilled a shot into the outside of the net. Then in the 30th minute, Andre Toussaint worked his way into a wide-open shot at the top of the arc, which required a diving save by Eylander to keep the Battery off the board.

Eylander’s 12th victory and 12th shutout tied him with Portland’ Josh Wicks for the league lead in both departments. Eylander, who already has a wide lead in saves, made four more on Sunday, giving him an even 100 for the season.

Montreal, which also has a shot to catch the Sounders for first place, also went down to defeat on Sunday, falling to Carolina, 1-0. The Impact have a 12-5-8 record and 44 points with three games remaining.

Two Sounders went to the sidelines with injuries. Midfielder Josh Gardner left midway through the first half with a sprained left ankle. He will have it X-rayed on Monday. Midfielder Kenji Treschuk went out in the 82nd minute with a foot injury.

After Friday’s game against California, the Sounders play host to FC Dallas of Major League Soccer in the U.S. Open Cup semifinals next Tuesday at 7 p.m. at Qwest Field. Ticket information is available by contacting the Sounders at (206) 622-3415, or online at seattlesounders.net.

Sounders 1, Battery 0

First half -- 1, Sea: Sebastien LeToux, from Hugo Alcaraz-Cuellar, 43rd minute.

Second half -- None.

Shots -- Chrls 9, Sea 19. Saves -- Chrls (Keith Wiggans) 5), Sea (Chris Eylander) 4. Corner kicks -- Chrls 4, Sea 10. Offsides -- Chrls 1, Sea 5. Fouls -- Chrls 15, Sea 13. Cautions -- Chrls: Stephen Armstrong 13th minute; Kenny Uzolgwe 28th; Tim Karalexis 59th; Kevin Nylen 77th. Ejections -- Chrls: Gordon Chin 78th. Attendance -- 4,291.