With 13 points from five matches, Ventura County (4-0-1) finds itself a point back of Fresno (4-0-2) with a match in hand.
The defending Southwest Division champion can return atop the standings Saturday night with a win against the host Southern California Seahorses at La Mirada High.
But the road trip holds greater importance. It will determine whether the Fusion qualify for the Lamar Hunt U.S. Open Cup for the second straight year.
Fresno has swept its four qualifiers with a plus-10 goal difference. Having swept its three qualifiers with a plus-9 goal difference, the Fusion can qualify from its eight-team group by winning by a two-goal margin or by scoring three or more goals in a win.