NHL owners and players are getting back to the bargaining table after a one-day break.

Negotiations are set to resume Sunday afternoon, although the sides are still working out the details. Talks took place for four straight days this week before heated discussions ended the run on Friday night.

The sides were in contact during the day on Saturday, leading to a small, informal lunch meeting in the afternoon. The decision to formally meet again was made Sunday morning.

Discussions turned sour on Friday a few hours into a bargaining session on the core economic differences that separate the sides and threaten the season completely.

The lockout is in its 57th day and has already caused the NHL to call off 327 regular-season games, including the New Year's Day Winter Classic.

A lockout wiped out the entire 2004-05 season.