With half an hour to go, it was Ulster who scored the first points of the second half when McCormick got over for his second try of the game, this time scoring from a tap and go from five metres out.
Ulster would spend 10 minutes of the second half a man down after Harry Sheridan was sent to the sin bin for a high tackle, but Ospreys could not make the most of their numerical advantage.
While they did score from a well-worked tap penalty as Tom Florence’s floated pass put winger Giles over in the corner, the missed conversion ensured they lost the sin-bin period 7-5 after Stockdale grabbed his second try and Nathan Doak added the extras to finish off the scoring.
Ulster: Lowry; Kok, Carson, McCloskey, Stockdale; Morgan, Cooney; O’Sullivan, McCormick, O’Toole; O’Connor (capt), Sheridan; Izuchukwu, Marcus Rea, McCann.
Replacements: McElroy, Reid, Wilson, Treadwell, Matty Rea, Doak, Humphreys, Postlethwaite.
Yellow card: Sheridan
Ospreys: Walsh; Kasende, Boshoff, Williams, Giles; Edwards, Hardy; G Thomas, Parry, Warren; Greatbanks, Jones; Lloyd, Tipuric, Morris (capt).
Replacements: Lewis, Phillips, Iowerth-Scott, R Thomas, Gemine, Morgan-Williams, Florence, Nagy.
Yellow card: Hardy
