The attacks often fluctuated from end-to-end, and Victor Moses, who was a constant threat down the left for Wigan, pounced on a poorMatt Taylor backpass, rounded keeper Jaaskelainen, but fired his effort wide of the target.
Ulster produced intense pressure straight after the break with Tommy Bowe looking lively but poor handling by Matt McCullough and Andrew Trimble meant scoring opportunities were squandered.
However, Matt Hemsley, spokesman for the transport charity Sustrans Cymru, criticised the M4 relief road as "poor value for money", saying investment in public transport would do more to ease congestion.