George Atallah, the NFLPA's executive director, claims the one-minute "Let Them Play" ad, which was intended to run four times during Saturday's college football all-star game, was barred from the channel, which is operated by CBS, an NFL broadcast outlet.
"Once they saw it and realized it had a CBA-oriented message, they decided they wouldn't air it," Atallah told the Associated Press.
A CBS spokesman told the AP that the channel wouldn't have accepted an ad from the owners, either. An NFL spokesman said the league knew nothing of CBS College Sports' decision, had nothing to do with the decision and had no objection to anyone airing it.
The current labor agreement between the NFL and the union expires March 3, though the owners have already opted out of the contract, touching off suspicions that they will lock the players out after the deal expires.
The NFLPA-produced ad, now appearing on YouTube, shows an empty stadium with a padlocked gate, with unseen voices saying "Let us play' and 'Let them play.' NFLPA president Kevin Mawae appears in the ad, saying "We want to play," which also features the urging of viewers to sign a petition on the players' behalf.
NFL commissioner Roger Goodell and NFLPA executive director DeMaurice Smith met Monday in New York to discuss and set up negotiating sessions.