Updated

The Dodgers are taking defensive positioning to another level -- and the Mets are not happy about it.

The Mets contacted Major League Baseball on Friday after learning that the Dodgers intended to mark prearranged defensive positions in the outfield at Citi Field, according to major-league sources.

Baseball is aware that the Dodgers used a laser rangefinder to determine certain positions before the game, and is gathering more information on the matter, sources said. League officials are not aware of any in-game use of the device, which would be a violation of baseball's rules on electronics.

Dodgers officials did not respond to initial requests for comment.

Here, according to sources, is how the situation developed:

The Dodgers, after using the laser rangefinder, wanted to use markers on the playing surface to define the desired positions for their outfielders.

The Mets' grounds crew told club officials that the Dodgers informed them that if the markers were removed, Dodgers players would dig holes in the outfield with their cleats. The Mets then instructed their grounds crew to erase or obliterate anything they saw on the playing surface.

The incident raises the question of whether teams should be permitted to use electronic devices to establish defensive positioning before games, and whether teams should be allowed to leave markers on the field.

The Dodgers apparently did not use such markers in Friday night's series opener, which the Mets won, 6-5. Television cameras captured left fielder Howie Kendrick consulting notes that he kept in his back pocket to adjust his positioning.