The Major League Baseball Players Association plans to make an in-person labor proposal to the league on Monday, sources told ESPN, countering MLB's offer last week that did little to loosen the gridlock that has gripped the sport after the league locked out the players Dec. 2.

Should the players' offer do little to advance the negotiations that thus far haven't yielded any substantive progress, the scheduled start to spring training in mid-February will grow that much unlikelier. And the longer discussions on a new collective-bargaining agreement last, the more they jeopardize Opening Day on March 31.

The gap between the players and league remains significant, with the union seeking major financial gains in a number of areas and owners trying to hold firm with what they currently pay in salaries. Other issues players have said remain a priority include anti-tanking measures and fixing service-time manipulation.

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Any concessions players make in their offer could provide a roadmap to the negotiations. Before implementing the lockout, the league asked the union to drop three areas of discussion: earlier free agency for players, salary arbitration after two years instead of three, and changes to the revenue-sharing plan. The union did not agree to the condition when presented with it on December 1, and the league left the bargaining table, locking out the players hours later.

Forty-three days later, the league returned to the union with an offer that included paying players with two to three years of service based on a formula, slight modifications to the draft lottery it previously had proposed, and a mechanism that would reward teams with draft picks when top prospects who started on opening day rosters win awards.

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