Keane scored his three goals over a 20-minute span of the first half.
But even that might have been overshadowed by the L.A. substitution in the 77th minute, when Rogers was sent onto the pitch and became the first openly gay man to play in a major U.S. sports league.
He was greeted with a brief ovation by the crowd of 24,811 at Home Depot Center in Carson, Calif.
“The most important thing is today we got three points,” Rogers told ESPN2 afterward. “It’s a Western Conference game, and the guys played amazing. (Keane) was clinical in front of the goal, and it was a pleasure to watch. They made it easy for me.”
The Galaxy took 15 shots and put six on target. The Sounders didn’t take a shot until the 57th minute. They ended up with two, both off the mark.
Los Angeles (6-4-2) broke ahead in the 12th minute on a Sean Franklin goal -- but Keane had a hand in that one, too, as he took a pass from Marcelo Sarvas, worked the ball deep into the penalty area, and slipped a pass across to Franklin, who swept it in from close range.
Keane followed that with three straight goals.
His first came by getting to a deflected ball near the penalty spot and finishing cleanly.
His next two came on penalty kicks. The first of those followed a debatable whistle on a slide tackle by Djimi Traori, who seemed to clear the ball before making contact with the L.A. attacker. The second PK came on a clear foul by Brad Evans, which also drew a yellow card.
Sounders goalkeeper Michael Gspurning actually stopped the first penalty shot, but a re-kick was ordered when midfielder Mauro Rosales entered the penalty area before Keane struck the ball.
It was the first hat trick ever allowed by Sounders FC.
The second half was scoreless and mostly quiet until Sounders frustrations yielded a red card to Shalrie Joseph and a yellow to Eddie Johnson.
The ejection means Joseph will not be available for Seattle’s next league match, Saturday at Chivas USA.
That’s bad news for coach Sigi Schmid, who put together a Sunday lineup that lacked midfielders Osvaldo Alonso and Steve Zakuani due to injury, but for the first time included all three designated players: Rosales, Joseph and Obafemi Martins.
The loss also ended a six-game unbeaten streak and a three-game winning streak for Seattle (4-4-3).
The Sounders will travel across the country to Florida on Monday for their U.S. Open Cup match at the Tampa Bay Rowdies on Wednesday.
More Sports Headlines
Silvertips open season with 2-0 win Kam's back, time for Seahawks to find Jimmy Graham disputes claim he’s unhappy with role in Seahawks’ offense Angels rough up M’s in 8-4 win Bears’ Cutler, Jeffery out vs. Seahawks; Clausen to start NFL asks for expedited appeal of ‘Deflategate’ ruling Saints QB Brees to miss Sunday’s game at Carolina M’s notebook: Reports say GM search down to pair of finalists
Our new comment system is not supported in IE 7. Please upgrade your browser here.