Will be staying around Union Square tomorrow night if any BA's have recommendations for some bars close by. Thanks in advance.
Rye House on west 17th street usually has a pretty good tap list, if you're up for a little walk Blind Tiger on Bleecker Street is worth a visit as well.
Rye House is the closest but there is also Good Beer, Proletariat, Hop Devil Grill, and a few more within reasonable walking distance.