Baseball's streak of 21 consecutive years of labor peace is in jeopardy.

The owners will consider voting to lock out the players if the two sides cannot reach a new collective-bargaining agreement by the time the current deal expires on Dec. 1, according to sources with knowledge of the discussions.

A lockout would put baseball's business on hold, delaying free-agent signings and trades until a new agreement is reached. The winter meetings, a joint venture between the majors and minors scheduled to take place from Dec. 4 to 8 near Washington D.C., might still transpire, but without the usual frenzy of major-league activity.

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The possibility of a lockout stems from the owners' frustration with the players' union over the slow pace of the discussions, sources said. The two sides still have more than a week to complete a deal, but a number of significant issues remain unresolved.

"We don't negotiate in the press," commissioner Rob Manfred said. "We remain committed to the idea that we're going to make an agreement before expiration."

The head of the players' union, Tony Clark, declined comment.

Two veteran players with knowledge of the talks, however, said that the players will fight for what they believe are the core beliefs and foundation of the union.

Both spoke on condition of anonymity, due to the sensitive nature of the discussions.

"We are not afraid of a lockout," one of those players said.

Clark, who replaced the late Michael Weiner as the head of the union, is negotiating his first CBA. Manfred, by contrast, is bargaining for the first time as commissioner, but was baseball's lead negotiator for the previous three agreements.

The owners offered to resolve two of the biggest issues by offering a straight exchange, telling the players they would eliminate direct draft-pick compensation in free agency in exchange for the right to implement an international draft, sources said. The players, however, rejected the proposal, wanting no part of an international draft.

The competitive-balance tax -- the amount of the threshold, the size of the penalties -- is another point of contention. The two sides also are at odds over changes in the Joint Drug Agreement; a number of players spoke out in favor of a stronger program during the season, but for baseball to strengthen the agreement, the union wants concessions in other areas, sources said.

The owners' proposal to end direct draft-pick compensation essentially would create unrestricted free agency in baseball for the first time. But the union strongly opposes an international draft, in part because foreign-born amateurs do not have the same leverage and opportunities as their U.S.-born counterparts, including college, sources said.

Under direct draft-pick compensation, a team loses a selection for signing a free agent who received a qualifying offer, which this year was valued at $17.2 million. Draft-pick compensation still would exist under the owners' proposal, but only indirectly; a team that loses a qualified agent still would receive a bonus pick.

As one person on the players' side put it: "We aren't giving them something that affects 30 percent of big leaguers and probably 50 percent of minor leaguers in exchange for something that affects less than 20 players every year, especially guys who are staring $17 million in the face."

Foreign-born players accounted for 27.5 percent of those on the Opening Day rosters and inactive lists, according to baseball. Ten players received qualifying offers this offseason.

Clubs favor an international draft in part because it would enable them to pay less money to international amateurs. Baseball currently restricts money going to such players by assigning bonus pools to each team, but both sides agree the current system is flawed, sources said.

Among the perceived problems:

*A 25-year-old Cuban player who has never played in the majors can receive a bigger contract than a major-league free agent who is burdened by draft-pick compensation.

*U.S.-born players who are subject to a draft are treated differently than foreign-born players who are not.

*The international market is so corrupt that a new entry system for players from foreign countries is required.

Some, however, say that an international draft would be difficult to implement due to the large number of countries involved, and create other problems.

A source on the players' side said that the remaining issues are "nothing that reasonable and creative people can't resolve." A player involved with the negotiations agreed, but said that if pushed, the union "will fight."

"These negotiations are always a struggle," the player said. "Like any negotiation and at any time things can flip around. But rest assured there have been proposals made that make you wonder what their goals are.

"Hopefully we get some traction soon."