Offaly proved too strong for Westmeath in the second half as they powered to a 4-15 to 1-20 victory at TEG Cusack Park, Mullingar.
Offaly finished superbly, with Shane Dooley grabbing a hat-trick, and now await the winners of Galway/Dublin on 18 June.
At half-time on Saturday, however, it seemed as if the Lake County were on their way to repeating that result as they opened up a 0-12 to 1-4 interval advantage, with Offaly being comprehensively outplayed.
Offaly’s goal came from a Shane Dooley penalty after Shane Kinsella’s ball in found Dooley, only for Westmeath keeper Paddy Maloney to bundle him over. Dooley made no mistake with the penalty, as he rifled it into the top corner.
It was all Westmeath thereafter, however, as they racked up a succession of points.
Realising something needed to change to avoid a repeat of 2016, Offaly manager Kevin Ryan threw Joe Bergin and Paddy Murphy into the fray at half-time.
It was Murphy’s introduction which changed the course of the game and by the 50th minute Offaly were back within a score.
That drew a response from the Lake County and they pulled two points clear, only for Offaly to grasp back the initiative. They had to wait, however, until seven minutes from time before they hit the front – Emmet Nolan collecting possession before bursting away and blasting the ball past Molone in the Westmeath goal.
It was now all Offaly; Dermot Shortt fired over from 40 metres with Dooley then bundling home his second goal from close range, after Oisín Kelly’s initial effort had been well saved by Maloney.
But when Alan Devine replied for Westmeath with a free and a 65, followed by Killian Doyle raising the green flag in the second minute of injury-time, it seemed as if Westmeath weren’t dead and buried just yet. But Dooley’s third goal settled the tie.