Fly-half Callum Sheedy kicked a last-gasp penalty as Cardiff fought back from 26-12 down to beat Ulster 29-26 and open their Pool 3 account at the second time of asking.
The hosts need just six minutes to go ahead at Cardiff Arms Park when second row George Nott went over and Leigh Halfpenny added the conversion, and they increased their lead through winger Tom Bowen's 12th-minute try.
However, Ulster reduced the deficit to five points when hooker Tom Stewart crossed and Jake Flannery added the two points, and they were 14-12 ahead at the break after Flannery converted centre James Hume’s 39th-minute try.
Winger Werner Kok (above) touched down within four minutes of the restart to increase the visitors’ advantage to seven points, and then repeated the feat with 53 minutes gone to claim a bonus point, Flannery’s third successful kick making it 26-12.
Replacement Danny Southworth edged the Welsh side back into it with a 64th-minute try which was converted by Sheedy, but both sides were reduced to 14 three minutes later when Cardiff flanker James Botham and Ulster lock Harry Sheridan were shown yellow cards.
Sheridan’s team-mate Ben Carson joined him on the sideline as time ran down and the home side made their numerical advantage tell almost immediately, back row Dan Thomas going over for a fourth try to allow Sheedy to tie it up at 26-26 with seven minutes to play, and Sheedy’s penalty at the death proved decisive.
