Two-time champions Internacional secured the top spot in their Copa Libertadores group with a 1-0 victory over Bolivia's Club The Strongest.
Midfielder Valdivia struck the winner just before halftime at the Beira-Rio stadium on Wednesday when he met Eduardo Sasha's low cross with a first-time volley that left goalkeeper Daniel Vaca with no chance, reports Xinhua.
The result ensured the Brazilian outfit ended the group stage as Group 4 leaders, three points ahead of Ecuador's Emelec, who also progressed to the knockout phase.
Club The Strongest and Universidad de Chile were eliminated from South America's top club competition.
Sasha, reportedly being targeted by English side Manchester United, bemoaned Club The Strongest's dominance late in the match, which almost led to an equaliser.
"We can't afford to let that happen again," Sasha said. "We need be at our best for the full 90 minutes."