Both sides were finding it difficult to hold the greasy ball in the early stages but Ireland opened the scoring on 13 minutes when a move involving Gerry Hurley, David Joyce and Ballynahinch centre Morrow sent fullback Danny Riordan in for a try in the corner.
Joyce added a penalty minutes later and Riordan was in for his second try on 27 minutes after Joyce and Michael McGrath had combined well. Joyce added the extras for a 15-0 lead.
Peter Jericevich kicked a penalty for Scotland eight minutes before the interval but that was cancelled out immediately by a Joyce effort to leave the score 18-3 at half time.
Ireland enjoyed the better of the exchanges in the second half despite playing into the wind and Hurley extended their advantage with an individual try after 49 minutes when he gathered the ball on the 10 metre line and found a gap to score.
Ten minutes from time substitute Declan Lavery scored Ireland's fourth try after Ireland disrupted a Scottish lineout inside their own 22. Queen's outhalf McMaster entered the fray late on for his first Club International cap.
IRELAND CLUBS:
Daniel Riordan (Old Belvedere RFC); Cian Aherne (Lansdowne FC), Stuart Morrow (Ballynahinch RFC), Mark Roche (Lansdowne FC), Michael McGrath (Clontarf FC); David Joyce (Clontarf FC), Gerry Hurley (Cork Constitution FC) (capt); Colm McMahon (St. Mary's College RFC), Tyrone Moran (Lansdowne FC), Christy Condon (Dolphin RFC); Dean Moore (Old Belvedere RFC), Fergal Walsh (Terenure College RFC); Willie Earle (Lansdowne FC), Charlie Butterworth (Lansdowne FC), William Ryan (Cork Constitution FC).?Replacements: Ian Hirst (Clontarf FC) for Colm McMahon 5-17 blood, Andrew O'Driscoll (Cork Constitution FC) for Tyrone Moran, Ian Hirst (Clontarf FC) for Colm McMahon, Declan Lavery (Old Belvedere RFC) for Christy Condon all 52, James Ryan (Cork Constitution) for William Ryan 66, Sean Walsh (Cashel RFC) for Dean Moore, Neil Cronin (Garryowen FC) for Gerry Hurley, Ritchie McMaster (Queen's University RFC) for Danny Riordan, Barry Daly (UCD RFC) for Cian Aherne all 70.