Tensions between NFL owners and the players' union continue to rise as the season begins and the deadline for a new contract looms closer. If an agreement is not reached by March of 2010, owners have threatened a lock-out for the 2011 season. Already, union leaders are advising players to prepare for an off-season, and to put off any big expenses planned for the near future. Peace has reigned for 16 years in player-owner relations, and games have not been affected by labor issues since 1987, but that could soon change. The issue is mainly, though not entirely, about a salary cap for NFL teams that would support equity between smaller and larger franchises. There are proponents from both sides in the union. The players' salary cap was increased last year, and then withdrawn, as owners found themselves increasingly unable to pay. Players want an explanation for the withdrawal or an uncapped year in 2010.