Jacob Stockdale will play at full-back as Ulster seek their third win in this season's Heineken Champions Cup against Harlequins on Saturday.

Louis Ludik returns to the right wing with Luke Marshall partnering Stuart McCloskey in midfield.

England's Kyle Sinckler returns to Harlequins' front row in what will be his first game since the World Cup final.

Tevita Cavubati and Semi Kunatani are also brought into Quins' pack.

Sinckler, who was forced off with injury after just two minutes of the World Cup final against South Africa, returns as Harlequins seek to build on their win over Bath in the last round of European matches.

There are no changes to the English Premiership side's backline with Danny Care again partnering 20-year-old Marcus Smith in the half-backs.

For Ulster, Will Addison's suspension means Stockdale is shifted from his usual berth on the left wing, where Craig Gilroy is preferred to Robert Baloucoune.

Marshall returns at outside centre in place of Matt Faddes who scored two tries in Ulster's 29-5 win over Scarlets last Friday.

Two changes to the pack see Ireland duo Iain Henderson and Jordi Murphy named to start with Kieran Treadwell and Sean Reidy dropping out.

The northern province currently sit top of Pool Three having won their opening two fixtures.

A win over Harlequins would leave them well placed at the halfway stage, with Clermont and Bath meeting in the other Pool Three fixture on Friday night.

Ulster: Stockdale; Ludik, Marshall McCloskey, Gilroy; Burns, Cooney; O'Sullivan, Herring, Moore, O'Connor, Henderson; Reidy, Murphy, Coetzee.

Replacements: McBurney, Warwick, O'Toole, Treadwell, Rea, Shanahan, Johnston, Faddes.

Harlequins: Chisholm; Ismaiel, Campagnaro, Lang, Ibitoye; Smith, Care; Marler, Elia, Sinckler, Lewies, Cavubati; Kunatani, Robshaw, Dombrandt.

Replacements: Musk, Auterac, Kerrod, Lamb, Lawday, Landajo, Saili, Goneva.