Jacob Stockdale starts for Ulster in the first of their back-to-back Heineken Champions Cup ties against Harlequins this Saturday.

The Ireland international is one of five changes to the side that recorded a bonus-point victory against the Scarlets last Friday.

In the back three, Louis Ludik shifts to the right wing as the returning Stockdale comes in at full-back, while Craig Gilroy retains his spot on the left wing.

Luke Marshall comes back in to the midfield alongside Stuart McCloskey, while Billy Burns resumes the fly-half position and once again partners up with scrum-half, John Cooney.

The front row is the same for the third game running; Eric O'Sullivan starts at loosehead prop, Rob Herring will line out at hooker, and Marty Moore packs down on the tighthead side of the scrum.

Alan O’Connor retains his starting berth in the second row and is joined by Iain Henderson who comes in again to captain the team.

Jordi Murphy returns at openside flanker, alongside Sean Reidy at blindside and Marcell Coetzee at number eight. Adam McBurney, Andrew Warwick, Tom O’Toole, Kieran Treadwell and Matthew Rea will be the forward reinforcements, and covering the back line will be David Shanahan, Bill Johnston and Matt Faddes.

Ulster team: Jacob Stockdale; Louis Ludik, Luke Marshall, Stuart McCloskey, Craig Gilroy; Billy Burns, John Cooney; Eric O'Sullivan, Rob Herring, Marty Moore; Alan O'Connor, Iain Henderson; Sean Reidy, Jordi Murphy, Marcell Coetzee.

Replacements: Adam McBurney, Andrew Warwick, Tom O'Toole, Kieran Treadwell, Matthew Rea, David Shanahan, Bill Johnston, Matt Faddes.

Listen to live commentary of Ulster v Harlequins (3.15pm) & Munster v Saracens (5.30pm) on RTÉ Radio 1's Saturday Sport