St. Mary's are unbeaten in their last four outings against Dungannon but curiously have not won on their last three visits to the Stevenson Park venue.
Having recently reached the semi-finals of the Leinster Senior League Cup - they face Clontarf at home on November 15 - St. Mary's are one of the form sides in Leinster at the moment.
Dungannon, for their part, are six points clear at the top of the Ulster Senior League, having won their opening five matches and collected an extra four bonus points for tries scored.
Two Irish coaches will be in opposition on Saturday. St. Mary's are coached this season by former Ireland 'A' hooker Peter Smyth, who has recruited extremely well over the summer months. Australian Shaun McCarthy has arrived in as backs player-coach.
Dungannon are coached for a second season by Ballymena Academy PE teacher John Andrews and are relying on former Queen's University lock Michael Rainey to lead them into the top-eight at the end of the season.
IrishRugby.ie Prediction: Dungannon to win by less than 7 points
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