A late Neil McManus point proved the difference as Antrim reached the Walsh Shield final by beating Laois 0-18 to 0-17 after extra-time in Rathdowney.
McManus top-scored with 10 points, three of those in extra-time, in a game played in testing conditions.
The sides were level six times in the opening 29 minutes, before points from Tommy Fitzgerald and Stephen Maher gave Laois an 0-8 to 0-6 interval lead.
But seven points without replay paved the way for a narrow Saffrons success.
Laois had extended their lead to five points inside eight minutes of the restart, but Antrim took a 0-13 to 0-11 lead by the 55th minute, with those unanswered points - three from McManus, with Darren Hamill, Neal MacAuley, Paddy Doherty and Kevin Barry McShane also on target.
Laois led by a point approaching injury-time following a Willie Hyland sideline cut, but a late Matt Donnelly score forced extra-time.
The sides were tied twice in extra-time, but Antrim dug deep as McManus claimed the winning score.
Antrim will face Dublin Institute of Technology in the final, after the students overcame Westmeath by 3-13 to 2-5 at Lakepoint Park, Mullingar.
Meanwhile, there were mixed results in the Kehoe Cup for Ulster sides.
Derry advanced to a semi-final against Kildare following a 2-11 to 2-10 win over GMIT at Celtic Park.
The hosts led by 2-10 to 1-7 with 10 minutes remaining following a Brendan Quigley goal, but GMIT were gifted a lifeline late on following a Conor O'Donnell goal in the 68th minute.
However, Derry held out for a slender victory.
There was not as much luck for Armagh in Pairc Tailteann, Navan, as a second-half revival by the hosts ensured the Royals claimed a 0-15 to 0-11 win.
Armagh led by 0-8 to 0-4 at half-time, thanks largely to the efforts of Declan Coulter and Paul Breen.
Meath scored five unanswered points on the restart to take a one-point lead and moved four points clear in the final quarter to advance to a semi-final against Wicklow next weekend.