The student bar in UCD dosen't open on Sundays so there will be no cheap drink available. The options are 1. the sports bar in the sports centre on the other side of the campus (great pint of Guinness)(10-min walk to Belfield Park), or 2. the Montrose bar on the other side of the dual carridgeway (5 min walk to belfield park), but they may not be too happy to see a bunch of football hooligans.