The 24-year old centre-half, who signed a Designated Player contract with the Galaxy last week, headed home the Galaxy's third goal in the 75th minute after copping some stick from RSL defender Nat Borchers.
"There was a little bit of smack talk before the ball was hit," Gonzalez said. "Borchers was talking some smack, but I think I got the last laugh.
"I've been waiting for a set piece, and I think maybe a week ago I said hopefully more would be coming, and tonight I got one, which I'm really happy about. And I think I could have got two more. I'm happy with the one, and, hopefully, I can just built off that."
In addition to Gonzalez's goal, Galaxy skipper Robbie Keane netted a hat-trick as his side went fourth on the Western Conference table.