The 22-year old forward, who was signed as a Homegrown Player in December, has shown glimpses of his talent all campaign but had not yet put together a really consistent 90 minutes.
In the 5-0 SuperClasico triumph over the Goats, Zardes had a hand in the opening goal when he played in a pinpoint leftwing cross for Landon Donovan to tap back for Keane to fire home in the sixth minute.
Just over 15 minutes later, Zardes supplied another peach of a pass for Donovan to slam home from inside the six-yard box before he added the Galaxy's third in the 26th minute when he pounced on a deflected pass from Keane to slot home from an angle.
It was classified as a 'breakout' game for Zardes and his output was warmly welcomed by Keane who has been hoping for something of this nature for a while now.
"Gyasi was unstoppable today," said Keane after the match.
"That's what we've been waiting for and expecting from him since he walked in the door. To be fair for him, there's been a lot of pressure on him and people expecting probably too much too early.
"But he stepped up today, and you can see every week he's certainly getting better and better, and if he continues to play like that, he's a nightmare for any defender, because no defender wants to play against someone with his pace and his trickery."
And Donovan was delighted for Zardes who he feels has been working hard to improve over the course of the season.
"He was terrific tonight. He's been working all year on doing the things that he did tonight. And they haven't always come off during the season, but you can see him getting closer and closer," he said.
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