Cardiff Blues gave their Heineken Cup hopes a huge shot in the arm with a 36-19 win that also starved Sale of four tries and a losing bonus point.
Sale's Heineken Cup quarter-final hopes were left hanging by a thread after they were battered into submission by the Blues.
Victory for the Sharks at Cardiff City Stadium would have set up a winner-takes-all Pool Five showdown with French giants Toulouse in Stockport tomorrow week.
But three Ben Blair penalties and a long-range Leigh Halfpenny strike took the wind out of Sale, despite tries by their Fijian number eight Sisa Koyamaibole, England centre Mathew Tait and lock James Gaskell.
A 12-5 interval deficit proved too much to overcome amid the heavy downpours, and Cardiff put Sale out of their misery through second-half touchdowns from scrum-half Richie Rees, lock Bradley Davies and number eight Xavier Rush.
An immaculate Blair finished with 18 points and, although the Blues or Sale could still conceivably progress as a best runner-up, Toulouse are now overwhelming favourites for a quarter-final place.
A bonus-point victory over already-eliminated Harlequins in France tomorrow would be enough for Toulouse to win the group a week inside the distance.
And the Sharks could have few complaints after being knocked out of their stride by a more organised and direct Blues outfit, who comfortably preserved their unbeaten European home record this term.
Both Sale and the Blues now need to win their final pool fixtures next weekend - Cardiff visit Quins - and realistically hope that one of two best tournament runners-up spots comes from Pool Five.
Sale had lost on three of their four previous Heineken Cup trips to Wales, including a 22-7 defeat against the Blues in 2004.
But a powerful starting line-up featured five international backs - an England quartet of Tait, Charlie Hodgson, Mark Cueto and Ben Cohen plus Wales scrum-half Dwayne Peel.
Blues boss David Young included southern hemisphere imports Sam Norton-Knight and Paul Tito on the bench, with Richie Rees handed the task of shackling Peel, rather than Peel's Wales squad colleague Gareth Cooper.
The Blues knew there would probably be no way back in their group if they failed to win, and they were rewarded for a bright start when Blair booted a second-minute penalty.
But Sale hit back within five minutes, capitalising on indecision at the base of a scrum close to Cardiff's line as Koyamaibole powered over.
It was a soft score for the home side to concede, yet they quickly settled into a rhythm and kept Sale at a safe distance, largely through some robust work by Rush and Wales prop Gethin Jenkins.
Blair's second penalty edged the Blues in front, and Sale were given further food for thought 11 minutes before half-time when Halfpenny drilled a 50-metre penalty between the posts.
Trailing 9-5, Sale needed their forwards to match Cardiff's intensity, but another Blair penalty stretched the home advantage and secured a healthy interval lead.
It was effectively game over within eight minutes of the restart after Rees' blindside dart and Davies' short-range surge left Sale with a mountain to climb at 26-5 adrift.
Tait's well-worked try, converted by Hodgson, provided a glimmer of hope, but Blair's fourth successful penalty snuffed out any Sale revival.
Peel then limped off, giving Wales coach Warren Gatland possible cause for concern three weeks before his team's Six Nations opener against England at Twickenham.
Gatland has already lost ankle injury victim Mike Phillips from his early Six Nations plans, so any long-term damage to Peel would leave the New Zealander with a king-sized headache.
Cardiff went in search of further points during the final quarter, although an inevitable raft of substitutions on both sides disrupted any flow.
The Blues were content to hammer home their superiority up front - confirmed when Sale prop Martin Halsall was sin-binned - and Cardiff went all out for a bonus point.
Even when Sale desperately tried to run scraps of possession from inside their own half, they floundered on poor handling or sub-standard passing.
Gaskell scored wide out two minutes from time and Hodgson effortlessly slotted the touchline conversion, but it was a case of too little, too late.
And Rush's interception of a Hodgson pass took Cardiff past 30 points, despite the late sin-binning of their Wales flanker Martyn Williams.
For Cardiff Blues:
Tries: Rees, Davies, Rush
Pen: Blair, Halfpenny
Tries: Koyamailbole, Tait, Gaskell
Cardiff: 15 Ben Blair, 14 Leigh Halfpenny, 13 Casey Laulala, 12 Jamie Roberts, 11 Tom James, 10 Ceri Sweeney, 9 Richie Rees, 8 Xavier Rush, 7 Martyn Williams, 6 Andy Powell, 5 Deiniol Jones, 4 Bradley Davies, 3 Taufau Filise, 2 Gareth Williams, 1 Gethin Jenkins (capt).
Replacements: 16 T Rhys Thomas, 17 Sam Hobbs, 18 Gary Powell, 19 Paul Tito, 20 Ben White, 21 Gareth Cooper, 22 Sam Norton Knight, 23 Tom Shanklin.
Sale: 15 Nick Macleod, 14 Mark Cueto, 13 Mathew Tait, 12 Lee Thomas, 11 Ben Cohen, 10 Charlie Hodgson, 9 Dwayne Peel, 8 Sisa Koyamaibole, 7 David Seymour, 6 Carl Fearns, 5 James Gaskell, 4 Dean Schofield, 3 Martin Halsall, 2 Neil Briggs, 1 Eifion Roberts.
Replacements: 16 Marc Jones, 17 Gavin Kerr, 18 Rob O'Donnell, 19 Chris Jones, 20 Luke Abraham, 21 Richard Wigglesworth, 22 Jonny Kennedy, 23 David Docherty.
Referee: Romain Poite