Replacement officials could be on their way back to the NFL.

According to a report from ESPN, the league is set to begin hiring officials from the college ranks as its collective bargaining agreement (CBA) negotiations with the NFL Referees Association (NFLRA) have hit a stalemate.

The current CBA deal expires on May 31. And while that may seem like ample time for the league and the referees’ union to reach an agreement, the ESPN report casts doubt on whether a deal is likely.

“NFL owners are ‘alarmed’ by the state of negotiations with the NFL Referees Association and have authorized staff members to begin hiring and onboarding replacement officials in the coming weeks, league sources said Sunday at the start of the league meetings,” ESPN reported.

“The NFL began compiling a list of college-level officials to recruit earlier this month, and owners are expected this week to approve a sweeping set of replay enhancements to support replacement officials in preseason and regular-season games. A separate league source said that training of the new replacement officials will begin May 1.”

The task of replacing NFL officials is not as easy as just hiring new referees.

League owners have taken the liberty of approving enhancements to replay to ease the integration of the new officials.

The NFL reportedly offered the officials a six-year CBA with average annual increases of 6.45 percent. However, the package also included performance-based changes that the officials’ union has resisted.

From the NFLRA’s perspective, the league has been less than a willing negotiating partner.

“We gave them a counterproposal, and they rejected it. We asked them to give us a response, and they refused, as their lead negotiator, Larry Ferazani, said he was not authorized to do so at that point. They then got up and left,” NFLRA Executive Director Scott Green said, via Albert Breer of Sports Illustrated.

Some of the performance-based conditions in the NFL proposal included extending the probationary period for new referees from three years to five years, basing playoff assignments on performance rather than on superiority, and implementing additional training programs for struggling refs in the offseason.