Coach Matt Williams has recalled Ryan Caldwell, Bryn Cunningham and Simon Danielli to his 26-man Ulster Squad ahead of this Saturday afternoon's Heineken Cup tie against Harlequins at Ravenhill (1.35pm).
However, number eight Robbie Diack has been ruled out with a frature to the metatarsal in his right foot.
Belfast Harlequin Chris Henry has also been drafted into the extended panel as cover in the back row.
Williams will name his starting XV and panel of replacements on Friday
ULSTER SQUAD (v Harlequins):
FORWARDS: Bryan Young; Justin Fitzpatrick; Rory Best; Nigel Brady; Tom Court; Brendan Botha; Ed O’Donoghue; Matt McCullough; Kieron Dawson; Stephen Ferris; David Pollock; Chris Henry; Willie Faloon; Ryan Caldwell
BACKS: Clinton Schifcofske; Bryn Cunningham; Darren Cave; Andrew Trimble; Ian Whitten; Paul Marshall; Isaac Boss; Paul Steinmetz; Ian Humphreys; Mark McCrea; Paddy Wallace; Simon Danielli