The Pirates of Buccaneers were left all at the sea on Shannon's first visit to their Ballinasloe venue of Moher Road, when the champions blazed an eight-try trail.
Ireland Sevens flyer Brian Tuohy bagged two of that hefty haul as the league's top side racked up a 56-3 win - and their highest points tally of the season.
Buccs had drawn level at 3-3 thanks to a 18th-minute Justin Meagher penalty, but John McKee's men were hopelessly outclassed over the remaining hour.
Eoin Cahill, Tony Buckley, David O'Donovan, David Quinlan, substitute Tom Cregan and veteran Andrew Thompson also touched down for the visitors.
Shannon (46 points), Limerick rivals Garryowen (44) and Belfast Harlequins (42) are all guaranteed a semi-final spot now, with the latter having triumphed 27-23 over Cork Con at Temple Hill.
'Quins' John Anderson took over the kicking duties from injured fly-half Ian Humphreys, and helped 'Quins pick up their sixth bonus point of the season. He converted his own try - his second score in two games - late in the first half to send DC Gillespie's men in at the break, with a 15-14 lead.
Con fought back through a well-taken drop goal from Darragh Lyons and a Pat McCarthy penalty, but Matt Mustchin's late converted try settled the issue.
Scrum-half Gerry Hurley steered Garryowen to a 26-20 victory over UCD at a windy Belfield as he picked up a try and converted Paul Neville, Kieran Gallagher and Ross Callaghan touch downs.
At Castle Avenue, Clontarf were given a dose of Puma power as Felipe Contepomi's first start for Lansdowne saw the league's bottom side win out 19-7.
The win - only Lansdowne's third - sees the Dublin 4 outfit two points behind fellow strugglers Carlow and Dublin University with just a clash with Trinity to come.
They would have been just one point adrift of their relegation rivals had Johnny Murphy's late try not been ruled out for a foot-in-touch.
Leinster's Argentinian international Contepomi - who started alongside Ireland's Lion-to-be Gordon D'Arcy - converted first half tries from Niall Ronan and Greg Stafford, with Murphy adding a third on the restart.
Elsewhere, Peter Bracken was on target as Galwegians edged Blackrock 14-13, while Carlow came out 20-10 winners at Trinity as Ross Jackson and Brendan Curran grabbed second half tries.
In Division Two, Old Belvedere pushed themselves clear of a relegation dog fight - winning 19-8 at home to Midleton. The Belvo pack were on song as former Ireland Under-19 Kevin Barden netted the only try.
On an afternoon of heavy try-scoring up top, leaders Dolphin (five tries), UL Bohs (6) and St Mary's (8) all ran riot at home.
Leinster hooker Gavin Hickie turned in a man-of-the-match performance for Mary's - using his Sevens' experience to pocket three tries - in their 61-8 hammering of Young Munster.
Bective fell out of the play-off race as led by fly-half John O'Mahony - the scorer of 128 points before kick-off - Dolphin completed their 16-game programme with a 34-17 win.
The Cork side sit top on 57 points, but wins for lead chasers UL Bohs and St Mary's - two points back - could see them done out of promotion and a home semi-final draw.
In Division Three, Greystones secured the title at Dr Hickey Park, running five tries past Ards in a 34-12 win.
The Wicklow men secured promotion in a repeat of last year's Division Three final - and broke through the 500-point mark in their 15th game - as Rob Connolly, Peter Hipple, Stewart O'Connell, and centre pair Conor McNaughton and Alan Higgs crossed the visitors' whitewash.
Four-times capped former Ireland lock Davy Tweed did have the last laugh for Ards, scoring an injury-time try at the ripe old age of 45!
AIB League Results: Saturday, April 9
* Dungannon v Ballymena has been refixed for Wednesday, April 13 (kick-off 7.30pm) at Stevenson Park.
Dolphin 34 Bective 17, Musgrave ParkMalone 20 Old Crescent 20, Gibson ParkOld Belvedere 19 Midleton 8, Anglesea RoadSt Mary's College 61 Young Munster 8, Templeville RoadTerenure College 27 Ballynahinch 20, Lakelands ParkThomond 13 De La Salle Palmerston 20, Fitzgerald ParkUCC 32 Highfield 10, The MardykeUL Bohemians 44 Waterpark 17, Thomond Park
Ballina 0 Skerries 3, Heffernan ParkBanbridge 32 Queen's University 31, Rifle ParkBruff 10 Old Wesley 27, Kilballyowen ParkCity of Derry 22 Portadown 27, Judge's RoadConnemara 16 Suttonians 16, Monastery FieldGreystones 34 Ards 12, Dr Hickey ParkInstonians 12 Clonakilty 13, Shaw's Bridge