Tesco said up to 60pc of workers had turned up for work, allowing it to keep open during a campaign of industrial action at eight stores over its plan to put long-serving staff on new contracts.
The store is one of eight which are now being picketed and Mandate says another eight will also join the action on Friday. Bailieborough staff will be balloted on Wednesday, February 22.
Last year, Tesco wanted around 1,000 staff recruited before 1996 to transfer to a less favourable contract which has applied to all staff hired since then.
Staff at the Bailieborough store, which opened in 2008, have previously been before the Labour Courts regarding entitlement for pay for their 15-minute breaks.
Mandate members are commencing an indefinite strike in eight stores: Baggot Street, Ballyfermot Road and Clearwater Finglas in Dublin, as well as stores in Tralee, Longford, Navan, Tullamore, and Bray.
His comments come after Tesco called on Mandate trade union to accept a labour court recommendation to avoid strike action today.
Mandate Assistant General Secretary Gerry Light said the ball is in Tesco's court if they want the strike to end.
The union involved says the strike is totally avoidable.