Plaintiffs in the upcoming NCAA antitrust trial will not be able to introduce as evidence the recent decision that allowed Northwestern football players to vote on whether they wanted to join a union.

U.S. District Judge Claudia Wilken ruled Friday that lawyers for former UCLA basketball star Ed O’Bannon and 19 others may cite the decision by a regional director of the National Labor Relations Board allowing the vote in their trial brief, but may not introduce the findings as evidence once the trial begins.

The decision was part of a series of rulings covering outstanding motions in the case. As part of the filing, Wilken again ordered the trial that could reshape major college sports to begin June 9 in federal court in Oakland, California.