Lansdowne bagged their sixth consecutive win over St. Mary's - a well-judged 34-18 victory - to take third place in the Division One standings.
AIB LEAGUE: DIVISION ONE: Saturday, October 14
LANSDOWNE 34 ST. MARY'S COLLEGE 18, Lansdowne Road
Scorers: Lansdowne: Tries: John Coleman, Greg Stafford, Ron Boucher, Robbie Dolan, Paul Doran-Jones; Cons: Mana Ashford, Robbie Dolan 2; Pen: Ashford
St. Mary's: Tries: Jonathan Sexton, Peter Smyth; Con: Sexton; Pens: Sexton 2
On the main pitch at headquarters, Liam Toland's side were 12-0 up inside four minutes - winger John Coleman and centre Greg Stafford both broke through as Mary's failed to clear their lines.
Lansdowne turned around with a 29-10 buffer thanks to further tries from number eight Ron Boucher and full-back Robbie Dolan.
Mary's found solace in Ireland U-21 out-half Jonathan Sexton, who tallied up 13 points, and coach/hooker Peter Smyth also touched down but prop Paul Doran-Jones' try had Lansdowne out of sight.
New out-half recruit Mana Ashford, who hails from New Zealand, added a conversion and a penalty to push Lansdowne 15-0 ahead, after their early try exploits in the Dublin sunshine. Ashford's penalty was preceeded by a yellow card for Mary's hooker Matt Duggan for an off-the-ball offence.
Good lineout work from Leinster's Devin Toner, the 6ft 10in youngster was a constant threat on Mary's ball, helped pave the way for Boucher's 26th-minute score, with Leinster's Niall Ronan supplying the try-scoring pass. Lansdowne were also playing with a benefit of a considerable breeze.
With Ashford off with damaged ribs, Dolan came to the fore. After Sexton had dribbled through to score his try eight minutes before the interval, Dolan crept through for a converted try of his own when Mary's were turned over on their own tap ball.
Sexton's injury-time penalty cut Lansdowne's lead to 29-10, although the visitors' comeback hopes were truly dashed when Doran-Jones, a summer signing from Dublin University, scored just minutes into the second half.
Mary's, who finished a disappointing 11th last term, gained some consolation when, after Lansdowne had both their props - Doran-Jones and John Lyne - yellow carded in quick succession, they had a spell of dominance.
And their efforts were rewarded when Smyth, after a rare defensive lapse from Lansdowne, dotted down in the 77th-minute. Smyth is coaching the Saints alongside Steven Hennessy for the third consecutive year.
Lansdowne: R Dolan; N Walsh, G Stafford, C Casey, J Coleman; M Ashford, S Whelan; J Lyne, K Corrigan, P Doran-Jones, D Toner, A Maher, D Lavin, J O'Donovan, R Boucher.
Subs used: N Ronan for O'Donovan, A Geraghty for Ashford, R Niland for Casey, K Cleere for Lyne, G O'Meara for Corrigan.
St. Mary's: P Brophy; J Norton, S Grissing, K Douglas, J McWeeney; J Sexton, J Kilbride; C O'Byrne, M Duggan, R Sweeney, G Logan, S Bradshaw, W Duggan, H Hogan, M Donnellan.
Subs used: R Gannon for Kilbride, P Nash for W Duggan, V Ryan for Bradshaw, P Smyth for M Duggan.
Referee: Olan Trevor (Munster)