The American could not hold back the tears on the podium when her national anthem played in the Californian capital.

She triumphed on board Milano at the North American League West competition, taking place at Rancho Murieta.

After four combinations went clear to force a jump-off, Porter was the only rider to go clear again to seal the title in a time of 39.16sec.

Jenni McAllister, another American, and Legis Touch the Sun were second after picking up four penalties in the jump-off in a time of 38.34.

An American 1-2-3 was completed by Richard Spooner and Chatinus, who collected four jump-off penalties and finished in 42.47.

"Milano was so in-form tonight," said Porter, a native of Northern California. 

"I couldn’t have asked him to do anything better. 

"As long as I stay out of his way, he's unbelievable. 

"He just rose to the occasion.

"I wasn't sure if he was going to be nervous with the crowd, but in reality, he thrived on it. 

"In the jump-off, he felt solid, not nervous. 

"He basically was saying, 'don't mess this up for me today'".

Porter has moved up to fourth in the Western league standings, with 22 points.

Jenn Serek of Canada leads the way on 29, with all riders attempting to earn a place at the World Cup Final.