An early goal from Tommy Fitzgerald proved decisive as Laois ousted Antrim. 1-16 to 0-13, to set up a Leinster quarter-final meeting with neighbours Carlow.
Fitzgerald struck after six minutes for the only goal of the game at O’Moore Park in Portlaoise and the tonic gave the underdogs a great boost.
And with Zane Keenan outstanding, Laois had a platform to see off the challenge of an Antrim side who were hoping to win two games in the same season in the Leinster championship for the first time.
Antrim recovered from the concession of the early goal and after Jackson McGreevy and Neil McManus hit points, Shane McNaughton edged them in front after 20 minutes.
But Laois led at the interval by 1-6 to 0-7 thanks to some good points with Keenan becoming more influential in leading the attack for the home side.
The Saffrons, who saw off Westmeath in their opening game, enjoyed a good spell directly after half-time.
Neil McManus equalised with a free and then edged them in front with a 65, but Laois did not allow them build on that slender advantage and they picked off some fine scores from Keenan and Stephen Maher to pull three points clear.
The visitors again hauled them back as Conor McKinley and Paul Shiels found the range, but then Laois took over.
Willie Hyland pushed them into a lead they never lost with a fine point and with Brian Dunne, Keenan and Hyland in superb form they eased their way to a surprise victory.
Keenan had the luxury of blasting a late penalty over the bar as the Antrim challenge wilted and Laois will now fancy their chances of reaching their first Leinster semi-final since 2005 when they take on Carlow in the next round, with the winners of that game going on to meet champions Galway.
Laois beat Carlow in a preliminary round last year and have improved immensely under the guidance of new manager Seamus Plunkett.
Laois: E Reilly; B Stapleton, B Campion, J A Delaney; J Fitzpatrick, C Healy, G Burke; J Walsh, M Whelan; B Dunne (0-03), S Maher (0-04, 2f), Z Keenan (0-05, 0-01pen); T Fitzgerald (1-01), W Hyland (0-03), J Brophy.
Subs: N Foyle for Brophy (46 mins), B Duggan for G Burke (53 mins), C Dunne for Walsh (62 mins), PJ Scully for Fitzgerald (70 mins).
Antrim: R McGarry; C McKinley, A Graffin, B McFall; O McFadden, N McAuley, P Shiels (0-01); J McGreevey (0-01), T McCloskey; N McManus (0-5, 0-02f, 0-01'65), M Donnelly, E McCloskey; C Clarke, C Carson, S McNaughton (0-05, 0-05f).
Subs: D Hammill for Clarke (35 mins), KB McShane for Donnelly (35 mins), R McCloskey for McGreevey (45 mins), S Casey for E McCloskey (57 mins).
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