They suffered a 3-2 defeat to their East Lincs Combination Division One rivals at London Road.
Old Boys are in knockout action again on Saturday when they host Sutton Rovers in round two of the Lincs Junior Challenge Cup. Kick-off is 1.45pm.
In Division Two, AFC Louth were sunk by substitute Jordan McEwan at North Cotes.
The visitors were edged out 5-3 with McEwan coming off the bench to score twice.
AFC Louth remain eighth and, like Louth OB Reds, are without a fixture this weekend.
But Division Two title chasers Alford Town return to action on Saturday after a blank weekend with a home tie against AFC Grainthorpe in the Tim Sales Charity Cup.
Only two fixtures took place in Division Three, with Mablethorpe Athletic Sports going down 3-0 at Market Rasen Town Reserves.
Louth Old Boys Vets’ trip to Grimsby Borough Development B was postponed.
This weekend, it’s the Vets’ turn to host Grimsby in the Tom Sandys Cup.