NBA owners, players and their union negotiators met for five hours in a last ditch bid to resolve their contract dispute and save the scheduled start of the regular season. Negotiators for the owners and union brass Sunday failed to agree how league revenues will be shared as the deadline for starting the season on time draws near. The two sides pledged to resume talks on Monday. "We're not necessarily any closer than we were going in tonight, but we'll be back at it tomorrow and we'll keep putting time in," union president Derek Fisher of the Los Angeles Lakers. NBA commissioner David Stern said earlier that if they fail to hammer out a new deal by Monday then the first two weeks of the regular season would be cancelled. The two sides still have three weeks before the opening day of the regular season on November 1. All of the NBA's 114 pre-season games have already been wiped out by the contract dispute, over which the league locked out players on July 1. The warring sides have met occasionally over the past few weeks as the NBA reportedly continued to insist it wouldn't move beyond the 50-50 split in league revenues that Stern proposed on Tuesday. The union rejected that, saying players wouldn't resume talks with any preconditions. According to the New York Times, it wasn't clear if the league is now willing to move off of its 50-50 proposal, or whether the union has softened its insistence on receiving 53 percent of league revenues in a new deal. They received 57 percent of "basketball related income" under the old deal. Team owners and players have been haggling over how to divide $3.8 billion in annual revenues and over salary cap issues. The gaps in their positions has been so wide it could jeopardize the entire 2011-2012 campaign. The only prior NBA season shortened due to money issues was in 1998-99 when the campaign was cut to 50 games per club because it took so long to reach a deal. Only once in American sports history has an entire season been lost to players and team owners being unable to agree upon financial terms, that being the National Hockey League's lost 2004-2005 campaign. NHL owners lost the entire season but generally were able to impose conditions they wanted in the eventual contract, which expires next September. Some owners of NHL teams that suffered through that missed season are among the NBA club owners who are involved in the latest deadlock.