Pro12: Glasgow Warriors v Ulster (Fri)

Luke Marshall receives treatment for his injury during the Scarlets game in Belfast

Ulster winger Craig Gilroy and centre Luke Marshall have been ruled out of Friday's Pro12 game against Glasgow.

Gilroy sustained a toe muscle injury in last Friday's win over the Scarlets while Marshall suffered a concussive injury in the same match.

Rory Best is likely to enter the fray as a replacement, with Jared Payne also set to be involved at some stage.

Prop Kyle McCall is a doubt for the Scotland trip after picking up a side abdominal injury against the Scarlets.

Best and Payne have yet to feature for the Irish province yet this season following their participation in Ireland's summer tour to South Africa.

Joint-skipper Rob Herring is likely to continue in the number two shirt, with Best being introduced during the second half.

Payne has overcome a calf problem picked up at an Ireland training camp at Carton House last month.

Winger Jacob Stockdale remains out with a toe injury and is expected to be available in a fortnight.

Ulster's injury bulletin on Tuesday also includes the news that Andrew Trimble's return to action has been delayed by a further week because of minor foot injury.

In the absence of Trimble, Gilroy and Stockdale, Rob Lyttle is likely start as Ulster attempt to halt a disappointing run of five defeats in their last five visits to Scotstoun.

Bowe boost

Fellow Ireland wing Tommy Bowe (knee) and lock Dan Tuohy (ankle) should "soon be available for selection" following long-term lay-offs.

Flanker Chris Henry (shoulder) and prop Wiehahn Herbst (groin) are pencilled in for their comebacks within the next six weeks.

Front-row pair Ricky Lutton and Johnny Murphy (both groin) are set to return in two-to-three weeks.

Unbeaten Ulster are second in the Pro12 standings while the Warriors, who lost for the first time this season at Cardiff Blues last Friday, are two points behind in fourth.