NEW YORK — NBA owners and players ended a marathon negotiation session early Thursday after meeting for more than 15 hours in talks aimed at ending the lockout.

They'll return to the table Thursday afternoon.

"We were able to work through a number of different issues today regarding our system," union president Derek Fisher said. "We can't say that major progress was made in any way, but some progress was made on system issues. Obviously enough for us to come back at 2 p.m. (Thursday)."

Union executive director Billy Hunter said the two sides did not discuss the distribution of basketball revenue, which has been one of the biggest obstacles to a deal.

The revenue split emerged as such a roadblock last week that Hunter said they should "park" the issue and turn the discussions back to the system, saying that players might be willing to take a lower number if they found the system rules more favorable.

NBA Commissioner David Stern said he hopes to build upon the progress made Wednesday.

"We're not going to talk about the particular progress," he said. "The energy in the room has been good; the back and forth has been good."