The Irish province will be back in Europe’s premier cup competition next season after coming out on top in the first ever Pro14 Champions Cup play-off showdown at the Kingspan Stadium.
Gilroy crossed late in the first half and early in the second to put Ulster in front after Ospreys captain Alun Wyn Jones ploughed his way over from close range following a rolling maul 15 minutes in.
Ulster raised their game after the break in the absence of the injured Rory Best, Iain Henderson, Charles Piutau and Ross Kane, with Kieran Treadwell and Jacob Stockdale also touching down and John Cooney scoring 15 points from the tee.
Jeff Hassler scored a five-pointer on the hour mark and Biggar signed off with a try in his last Ospreys match before joining Northampton Saints, becoming the leading points scorer in the history of the competition with 1,585.
It was Ulster, though, who deservedly qualified for the Champions Cup after finishing fourth in Conference B.
— Ospreys (@ospreys) May 20, 2018
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