Oeste defeated De Piracicaba 3-0 at home to record a fourth win in five matches and move up to ninth in the Campeonato Paulista.
After a first-half stalemate at Estadio dos Amaros in Sao Paulo, Dezinho broke the deadlock for the hosts in the 54th minute.
Serginho doubled the advantage 12 minutes later with his fifth goal of the campaign before midfield partner Wanderson rounded out the scoring on 72 minutes.
The win continues Oeste's strong response to a lacklustre start to the season, Luis Carlos Martins' side moving within one point of eighth-placed Corinthians, who occupy the final playoffs place with a game in hand.
De Piracicaba stay 14th after a third defeat in four matches but could slide into the relegation places after the weekend fixtures.
Friday's other match ended in scoreless draw between Uniao Barbarense and Bragantino, who sit in 19th and 10th place respectively.