The duo will take over the lion's share of playing time at the position.
The Mets are planning on using recently-recalled left-handed hitter Matt den Dekker and right-handed hitter Eric Campbell in left field now that the team has cut ties with Chris Young. While they hit from different sides of the plate, both players have spent the majority of their professional careers in the minors. Campbell is 27, and den Dekker will turn 27 tomorrow.
While neither player has played enough in the big leagues to draw conclusions about their platoon splits, both players have long track records of hitting well against opposite-handed pitchers. There's no guarantee that either player will succeed at the major league level in the long run, but it makes sense for the Mets to try the platoon out for now and see how it goes.
Of course, assuming Terry Collins sticks to his plan, Eric Young Jr. figures to see very little starting playing time. Given his struggles at the plate this year, that, too, makes sense.