Boston Town picked up a valuable point at Newport Pagnell Town on Saturday.
Jack Wightwick gave the Poachers a 1-0 interval lead at the highflying Swans, who had thrashed Harrowby United 10-0 the previous weekend.
It was in-form Wightwick’s eighth goal in 10 appearances so far this campaign.
A second-half spot kick sealed a point for the Buckinghamshire side, but Town held on against the hosts, who could have gone top of the United Counties League Premier Division had they won.
Town’s home game against Deeping Rangers, scheduled for on Wednesday has been postponed.
It will be rearranged at a later date because Rangers have a midweek FA Vase replay against Walsham le Willows.
If Deeping win they will actually play the Poachers in the next round on 24 September.