During his visit to Mets camp Thursday, union chief Michael Weiner said there will be more equity in interleague play beginning in 2013. Still, Weiner noted, the Mets and Yankees as well as other natural rivals will continue to play.

Once the Houston Astros move to the American League West in 2013, each division will have five teams. As a result, Weiner said, for the most part the NL East teams largely can all play the same opponents in interleague, except for any adjustment to preserve series such as Mets-Yankees.

An MLB official noted, however, that it is "much more complicated than that and there will be more than 15 interleague games."

Said Weiner: "With five teams in each division, you can now have a much fairer interleague-play schedule, because each of the five teams in the National League East, for example, will play the same competition in the American League Central or the American League West or whoever they're matched up against.

"There will be a deviation to allow for those natural rivalries. It means that with the exception of that deviation, the schedule for division rivals will be virtually identical. It's not going to be 162 out of 162, but it's going to be much closer than it was able to be in a world where you had four-, five- and six-team divisions to try to match up."

• Mets officials believe a pool of players will become available with five days remaining before Opening Day because of a provision in the new collective bargaining agreement. A player with major league experience who signed with a team this past offseason on a minor league deal will become a free agent five days before the regular-season opener if he fails to make the major league club unless he is paid a $100,000 retention bonus.

Teams wary of forking over that dough in order to preserve organization depth may cut some players loose.

"When we negotiated that provision, it was to protect veteran major league players who are under minor league deals," Weiner said. "Because from our experience -- talking with those players and talking with their representatives -- they want to know [their fate]. If they're not going to make a team, the ability to be out there as free agent five days before Opening Day gives them a chance given other roster fluctuations to find some place to go.

"So I don't know how that's going to play out. But if it does lead to a number of veteran players getting an opportunity to sign with another organization, where they have a better chance to get to the big leagues as opposed to ending up buried in a minor league organization where they don't have a chance, then it accomplished what we wanted it to."

• The union fundamentally opposes teams who lose free agents getting draft picks as compensation for the player departing.

That's because if the signing team potentially has to give up a first-round pick to sign a free agent, it might depress the number of teams bidding and therefore the size of the resulting contract.

The new CBA makes progress in that respect for the union. Now, any player traded midseason during the final year of his contract would not command draft-pick compensation if he then left the acquiring team next winter as a free agent.

For instance, if David Wright were traded in July and then became a free agent next offseason, whichever team acquired and then lost Wright would get no draft choices -- a change from past practices.

"We don't like draft-choice compensation," Weiner said. "We think it hurts players in free agency. So we're doing everything we could to try to have as few players as possible subject to draft-choice compensation. We also thought, and the owners agreed, that draft-choice compensation, part of it is designed to try to achieve competitive-balance objectives. In that kind of situation it's somewhat complicated as to whether it really is."

• As he makes his way through camps in Arizona and now Florida, Weiner said, the Ryan Braun case in particular and blood testing in general has been a topic of discussion between the union and its members. Weiner said there are not complaints -- just curiosity.

"That's healthy," Weiner said. "When the players get the answers to those questions, I don't think they have any concerns. I actually am disappointed if I walk into a clubhouse and don't have questions, whether it's on the drug program or anything else. And this [Mets] clubhouse was no exception. We had plenty of good questions."

Weiner said 2013 could bring in-season blood testing for HGH. The new CBA does not mandate in-season blood testing to begin that season, but the language calls for the sides to discuss/consider it. Weiner said players are receptive to instituting it after regular-season games.

• With interleague play set to be continuous throughout the season in 2013 because of an odd number of teams in each league, Weiner said making the DH rule the same in both leagues came up from neither side in CBA discussions and will remain the same. Pitchers will continue to hit in the NL. The DH will continue in the AL.