Garryowen edged past a rejuvenated Shannon at Dooradoyle on Friday night in a Limerick derby match which did not live up to expectations.
Neither side could manage a try but it was all about the result between these two great rivals and Garryowen will be relieved to maintain their great start to the campaign while Shannon picked up their first point of the season, albeit a losing bonus one.
Out-half Jamie Gavin landed Garryowen's first penalty after eight minutes but it was all square after 27 minutes when his opposite number Rob Guerin was on target for the under-fire visitors.
Guerin started at out-half but moved to his more regular scrumhalf position when Mike D'Arcy was injured in the second half.
A big improvement was expected in the second period but it remained a battle of the place-kickers all the way.
Gavin kicked four in the end for Garryowen and his last strike was eleven minutes from the end which left it 12-6 after Guerin had landed his second Shannon penalty.
Shannon, whose coaches Stephen Keogh and Eoin Cahill stepped down last Monday, needed a try if they were to snatch victory but they could not breach a strong Light Blues defence.
There were notable performances from Munster's Ronan O'Mahony and Luke O'Dea at full-back for their respective sides, the pair both swept up well in defence and threatened with ball in hand on occasion.
The result leaves Garryowen just a single point behind table toppers Lansdowne, while the losing bonus point will give Shannon something to build on for next weekend's home clash with defending champions St. Mary's.
Referee: Paul Haycock (IRFU)