Traditionally the New York Mets and New York Yankees have been two clubs engaged in an adversarial relationship, not due to sharing a division or conference, but rather a city. It is not adversarial on the field, as in a traditional rivalry such as with the Yankees and Boston Red Sox.
However, the divisions are deeply rooted in each organization, where resentment stems from both sides. Perhaps, not evenly, though.
The Wilpons, owners of the Mets for over 15 years, have begun to harbor a great deal of resentment towards the far superior, in terms of achievements, Yankees.