The 2011-12 NBA season moved closer to cancelation Monday as the players union rejected an offer considered to be an ultimatum from owners and NBA commissioner David Stern.

The NBA season had been scheduled to begin Nov. 1 but has been delayed indefinitely to this point. Though it’s too soon to conclude there won’t be any pro games at all this winter — the last NBA labor dispute was resolved in January 1999 in time to play a 50-game regular season plus playoffs — Monday’s news ratcheted up the possibility that the season would be scratched entirely.

“It looks like the 2011-12 season is really in jeopardy,” Stern said in an interview with ESPN’s “SportsCenter.”

TNT, which uses the NBA not only as a ratings magnet but to supplement and promote its regularly scheduled primetime programming, would be the network most affected if the season is scrapped. In place of the “NBA on TNT” on Thursday this week, for example, the cabler is airing syndicated episodes of “Bones” and “CSI: NY.”

The network declined to elaborate on contingency plans if the entire season falls by the wayside.

ESPN, as well as local cable channels, will continue to use college sports, especially with the college basketball season now under way, to fill in its programming gaps. Overall, ESPN and TNT had 127 regular-season game broadcasts scheduled entering the 2011-12 season.

NBA players are moving toward decertifying their union as a means to sue the NBA on antitrust grounds with the possibility of winning billions of dollars in triple damages. The NBA has already countered with a lawsuit against the union and a complaint with the National Labor Relations Board.

The Associated Press reported that attorneys David Boies, who represented Al Gore following the 2000 presidential election, and Jeffrey Kessler, would lead the players’ legal team. In the recent NFL players-owners dispute that threatened to short-circuit the football season, Boies and Kessler were adversaries, with Boies working for the league.

At the heart of the dispute is how the league’s basketball-related income should be divided. Players, who were guaranteed 57% in the last collective bargaining agreement, are being asked to accept a 50-50 split or a sliding scale that’s pinned to the rise and fall of the sport’s total revenue.