Shannon failed to score a try but did enough to warrant this tight win over Division 1A opponents St. Mary’s College at Thomond Park.
The Limerick side got over the finish line thanks to four crisply-struck penalties from out-half Gareth Quinn McDonogh, along with drop goals from Quinn McDonogh and winger David O’Donovan.
Playing into a slight wind in the opening half, hands in the ruck allowed full-back Gavin Dunne kick St. Mary’s into a seventh minute lead.
His opposite number Luke O'Dea raced forward on a 30-metre break which led to Quinn McDonogh's first successful penalty of the afternoon.
St. Mary’s moved the ball at pace, looking to get wingers Darragh Fanning and Conor Hogan involved in as much play as possible.
Shannon, favouring a tighter approach, lost a number of decisions at the breakdown. One of them saw Dunne kick the Dubliners back in front in the 23rd minute.
The hosts were on level terms seven minutes later, Quinn McDonogh drilling over his second penalty goal after good work from the Shannon lineout and a notable surge from player-coach Stephen Keogh.
Keogh and company held the edge up front, their scrum building on the progress made in recent weeks. Quinn McDonogh suffered his first penalty miss, but the young number 10 quickly redeemed himself with a 35-metre drop goal as half-time approached.
Turning around with a 9-6 buffer, Shannon used their maul to good effect. It drew an infringement from Mary's and Quinn McDonogh swept over the resulting penalty.
Shannon mauled again from another lineout in the Mary's half and with a penalty advantage, the experienced O’Donovan stuck over his drop goal for a 15-6 scoreline.
The visitors showed great determination in the final quarter, winning the territorial battle albeit with Shannon holding their defensive line intact.
Peter Smyth’s charges kept plugging away and were rewarded in the 70th minute. Lock Stephen Bradshaw, his grandfather of the same name a lifelong Shannon club member, took the ball on after a crooked lineout throw and from the resulting drive prop Rob Sweeney burrowed over from two metres out.
Despite that try, Shannon managed to stave off Mary's late assaults and Quinn McDonogh sealed Shannon's third victory on the trot with an injury-time penalty from the 22.
Referee: Michael Black (IRFU)