WASHINGTON -- The National Labor Relations Board said Thursday that it will stay the decision by a regional NLRB director who said scholarship football players are employees and should be allowed to unionize. The NLRB acted on a request from Northwestern, which opposes unionization, and said the request "raises substantial issues warranting review."

A secret ballot election of the football players that had been planned for this morning will still take place, but the ballots will be impounded and the results kept secret "until the board issues a decision affirming, modifying or reversing the regional director's decision," the NLRB said in a statement. Impounding ballots is common in cases in which the NLRB is reviewing a dispute about a proposed bargaining unit.

"The board intends to issue a subsequent notice establishing a schedule for the filing of briefs on review and inviting amicus briefs," the order says, "to afford the parties and interested amici the opportunity to address issues raised in this case."

Through appeals, the case could ultimately end up in federal court.

Northwestern spokesman Alan K. Cubbage said in a statement that the university is "pleased" with the review, and would begin preparing and gathering briefs. He noted that it could be months before the board decides whether the athletes are employees.

"We agree that there currently are important issues regarding college athletics nationally and that students should have a voice in those discussions," Cubbage said. "However, we believe that a collective bargaining process at Northwestern would not advance the discussion of these topics, in large part because most of the issues being raised by the union are outside the purview of Northwestern."

The board's decision is not entirely surprising. The unionization movement and the regional director's decision has been a subject of intense public and media interest, particularly in the context of other challenges to the National Collegiate Athletic Association's power, including lawsuits over scholarship caps, use of likeness and safety issues. The regional decision was unprecedented and raised a number of questions regarding potential tax issues, workers' compensation and Title IX.

When the Northwestern quarterback Kain Colter and the National College Players Association announced they'd co-founded the College Athletes Players Association, many predicted they'd have a tough time. But testimony before the regional director focused on long hours spent on sports, pressure to take easy courses, and restrictions on athletes' eating and travel. In exchange for compensation in the form of a scholarship, Director Peter Sung Ohr said, athletes performed services for an employer (in the form of Northwestern).

The university filed a formal appeal two weeks later, asking the full NLRB in Washington to intervene.

"Based on the testimony of a single player, the regional director described Northwestern's football program in a way that is unrecognizable from the evidence actually presented at the hearing," Northwestern said in its brief.

The union would advocate for better safety rules, scholarships and medical coverage, its organizers say.