Clare came good in the second half at Thurles to defeat Waterford by 2-20 to 1-15 in the Munster SHC.
Jake Dillon marked his Waterford debut with a first-half goal that helped his side to a 1-9 to 0-8 interval lead.
But Clare dominated after the break, with Shane O'Donnell and Conor McGrath hitting goals.
Colin Ryan chipped in with a seven points tally as Davy Fitzgerald's side cruised home to set up a semi-final clash with Cork.
Second half goals from Mark Poland and Donal O'Hare saw James McCartan's side come from four points behind to win by five and set up a semi-final clash with All-Ireland champions Donegal.
Mark Lynch smacked in a first half goal to give the Oak Leafers an edge, but Down had the edge in finishing power to finish strongly with inspirational scores from midfielder Kevin McKernan.