All teams are aiming to dethrone County champions St Rynagh's.
The Molloy Environmental Systems Offaly Senior Hurling Championship gets underway tonight with three games down for decision.
In Group 1, Clodiagh Gaels take on Kinnitty in Banagher while Birr face Kilcormac-Killoughey in Rath.
In Group 2, Ballinamere face Shinrone in Lusmagh.
All three games throw-in at 8pm.
Tomorrow in Group 2, there's the meeting of Belmont and Seir Kieran in Birr at 4pm.
The Senior B Hurling Championship also gets underway tomorrow with Lusmagh facing Tullamore (Kilcormac, 6pm), Drumcullen taking on Birr (Kinnitty, 7pm) and Clara facing Kilcormac-Killoughey (Killeigh, 7.30pm).