Ulster Director of Rugby Les Kiss has made just three personnel changes to the Ulster team that will travel to Ospreys on Saturday afternoon.
Ulster travel to Swansea knowing playoff destiny still remains in their own hands with two regular season games remaining.
Ireland centre Stuart McCloskey is drafted in to start at inside centre where he will partner Luke Marshall in midfield.
The other backline change sees Craig Gilroy brought in at full back, while captain Andrew Trimble continues on the right wing and Charles Piutau is named on the left.
The experienced half back pairing of Ruan Pienaar and Paddy Jackson remain in situ.
Robbie Diack is the sole change in the pack as he will slot in at number eight, where he will be flanked by Iain Henderson and Sean Reidy.
Kieran Treadwell and Alan O'Connor will continue their second row partnership for the fifth game in a row, while the front row of Andy Warwick, Rory Best and Wiehahn Herbst is also retained.
Here is your Ulster team for Saturday's huge @PRO12rugby Round 21 trip to @ospreys. #SUFTUM https://t.co/otG9W6l5d3 pic.twitter.com/jxXukLhKNc
— Ulster Rugby (@UlsterRugby) April 28, 2017
Ospreys v Ulster at the Liberty Stadium on Saturday February 29 - 3pm kick-off.
: C Gilroy, A Trimble (Capt), L Marshall, S McCloskey, C Piutau, P Jackson, R Pienaar; A Warwick, R Best, W Herbst, K Treadwell, A O'Connor, I Henderson, S Reidy, R Diack.
: R Herring, C Black, R Ah You, F van der Merwe, N Timoney, P Marshall, S Olding, J Stockdale.