Leinster confirmed that they have signed Paddy Wallace

Ballymena prop Bryan Young has joined Paddy Wallace in signing a short-term contract for Leinster.

Both Ulster players will be used as cover by Leinster for the remaining stages of the Heineken Cup.

Neither player featured for Ulster in Europe this season and the competition rules allow two additional players to be registered to original squads for the knock-out stages.

Leinster have had major problems with fly-half Nathan Spooner missing most of the campaign while there are worries over centre Shane Horgan who has a troublesome thigh injury.

The loss of Ireland prop and captain Reggie Corrigan with a broken wrist was also a major blow.

With the unlikely prospect of former Lions tight-head Paul Wallace returning from a serious ankle injury, coach Matt Williams was prompted to seek cover in Young.

Young, 22, is a former Ireland under-21 prop and was on a development contract with Ulster.

Wallace was not included in Ulster's Heineken Cup line-up after he fractured his fibula during a Celtic League match against Swansea last September.

Wallace returned to full-time training last month when Leinster first showed an interest in signing the talented utility back on a short-term basis.

Leinster are due to face Biarritz at Lansdowne Road on Saturday, 12 March in the quarter-final of the Heineken Cup.