Bebe King, six, Elsie Dot Stancombe, seven, and nine-year-old Alice Dasilva Aguiar were killed in the stabbing in Southport on Monday.
Nine-year-old Alice was a pupil at Churchtown Primary School which is a few hundred yards from Southport Hesketh FC.
The club was planning it's own minute's silence on Saturday ahead of their home game with Holker Old Boys Reserves.
The league is now inviting all member clubs to hold their own minute's silence or applause on Saturday before their matches.
Five other children and two adults remain in a critical condition following the attack. A 17-year-old male from Banks - a village between Southport and Hesketh Bank - has been arrested on suspicion of murder.
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