Four clubs meet in O'Moore Park to fight for two places in the county final.
Portlaoise hold the edge over the remaining three clubs in the Laois Senior Football Championship, according to Rosenallis' John O'Loughlin.
The former O'Moore County star believes their performance in beating the defending champions St Joseph's last time out sets them apart.
The 35 times champions are looking to win their first championship since 2019 - they face O'Dempsey's in O'Moore Park on Sunday.
The competition's other semi-final pits Portarlington against Graiguecullen.
O'Loughlin says Portlaoise were impressive in beating last year's champions:
The action on Sunday begins with Portlaoise's game against O'Dempsey's at 2.15pm, Portarlington against Graiguecullen at 4pm.
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