The winger, who has also played for Dutch side Heerenveen and MLS outfit Columbus Crew, came off the bench in the 77th minute of a 4-0 victory over Seattle Sounders.
"No pressure at all, I got to totally enjoy myself and take it all in," the Californian said after the match, watched by a 25,000 strong crowd in Carson.
"Earlier today I was really nervous. Okay, this is a soccer game. I've done this a million times. But then obviously I know, I'm not naive, I know people are watching."
Rogers, 25, retired from the game after coming out in February, saying the emotional toll of closeting his sexuality led him to "step away" from football.
However, after a few months off and plenty of support from fans and fellow players, Rogers reversed the decision, moving back to his homeland and signing for LA at the weekend.
Another major US athlete - basketball player Jason Collins - came out as gay earlier this year, but he is a free agent and thus has not actually played a professional match after announcing his sexuality.
"It was really perfect. We won, which is most important. My family was here, my friends. My grandparents," Rogers added.
"I've kind of been on this huge journey trying to figure out my life. And now I'm back here. I think I'm kind of where I'm supposed to be."
The moment, which brought a big smile to Rogers as he took his position, held special meaning for many.
"Many years from now most people won't remember the score of this game. But they'll remember when he stepped on the field," former Galaxy executive and USA defender Alexi Lalas told the Los Angeles Times.
"That's cool. That's important."
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