The Cubs, who tightened up their defense in the second half, outscored the home team 15-9 in the third quarter to grab momentum and ran out to a 51-46 victory.
Tanner Curran continued to impress for South Fork, scoring a team-high 16 points, while Alex Harding added eight and Graham McConnell seven.
“I’m very impressed with how well the boys are playing with not a lot of practice,” said head coach Chris Contreras, whose team pushed Eureka in a 46-38 loss in its opener on Thursday. “Luckily for us most of our players have played together since the sixth grade.”
Ryder York added six points in the win, as the Cubs improved to 1-1.
Emmitt Albee continued to lead the way offensively for the Cats, scoring a game-high 18 points.
Teammate Javier Lopez added 14 points and Jenner Christiansen had six.
The Cats are now 0-3 after also dropping games to Del Norte and Arcata earlier in the week.