The delighted Irishman said: "It couldn't have gone better for me.
"When you come to a new team, it's always good to get the first goal.
"When you go a few games without a goal, it starts to play on your mind."
Keane, 31, was substituted after 72 minutes and received a standing ovation from the 27,000 crowd at the Home Depot Center.
His replacement Mike Magee bagged Galaxy's second goal as Bruce Arena's men stretched their lead at the top of the Western Conference to six points.
Galaxy stalwart Becks was impressed with the immediate impact made by new team-mate Keane.
And the midfielder revealed it was a pleasure to play in the same team as a striker with a true predator's intinct.
He said: "I knew he was going to be running and I knew where to put it.
"Keane's a player who knows where to run. If you're on the same wavelength as him, you've got a real good chance.
"He's always going to make good runs and it's up to us to find him."
Galaxy boss Arena added: 'We're elated with Keane. He had a great 70 minutes tonight and he's going to have a lot more.
"I know Robbie's fitness isn't perhaps where he wants it to be, but he's a fit athlete.
"When he gets two or three games under his belt he's going to be fine."