Piero Maza to Referee Boca Juniors vs. São Paulo in 2026 Sudamericana Quarterfinals

Piero Maza has a big date circled on his calendar. The Chilean referee has been assigned to one of the most attractive quarterfinal matchups of the 2026 Copa Sudamericana: Boca Juniors vs. São Paulo, set for Tuesday, September 8, at 9:30 p.m., at La Bombonera.

CONMEBOL confirmed the officiating crews for the first-leg matchups this Thursday, and there's an extra layer of intrigue: Maza won't be working alone. He'll be joined by a full delegation of fellow Chileans, with Fernando Vejar running the VAR and the assistant referees and fourth official also hailing from Chile. It's an all-Chilean crew for a match that promises tension from start to finish.

Why is this matchup generating so much buzz? Because it pits two teams that came out swinging in the previous round. Boca dispatched Deportivo Recoleta with a commanding 7-1 aggregate score, while São Paulo did its job by eliminating Bolívar. Now the two sides face off in a two-legged tie, with the return match set for Tuesday, September 15 at the Morumbis, on Brazilian soil.

Another Argentine Set for Colombia

The officiating assignments also include a notable detail to watch from the Argentine side, though this time it's about the officials rather than the players. Independiente Santa Fe will host Vasco da Gama on that same Tuesday, September 8, at 7:00 p.m., at El Campín stadium in Bogotá, with Argentine referee Darío Herrera holding the whistle.

Herrera won't be working solo either: his countryman Hernán Mastrángelo has been tapped to run the VAR for that match. It's another Argentine presence among this round's officiating assignments, even though the teams on the field are Colombian and Brazilian.

The series between Santa Fe and Vasco da Gama, like all ties at this stage, will be decided over two legs. The return match is set for September 15, when the Colombian side travels to Brazil to close out the tie.

With these assignments, CONMEBOL is beginning to shape the officiating for a round that hands out four tickets to the semifinals. And although the crews for the other quarterfinal matchups have yet to be confirmed, it's already clear that Boca and Santa Fe will share something beyond the hope of advancing: both will have heavyweight South American officials guiding their fate in this round.