Ourinhos, after winning the first two games at home by large margins, only scraped a 71-69 triumph at Sport Recife on Saturday with Brazil international Iziane scoring a game-high 27 points and Lisdeivi weighing in with 17.
Ourinhos didn't help their cause at the line, making just 11 of 19 (58%) for the game.
Jaqueline and Tayara each poured in 16 points in defeat for the hosts.
On Sunday, Catanduva hit the road and maintained their hegemony over São Bernardo, clinching an 85-76 in.
Natália had 24 points to pace the victors while Brazil international Cintia Luz also had 24 for the home side.
FIBA