Dan Cotton and TJ Nightingale were sent off as Spalding United slipped to a shock 2-1 UCL Premier Division loss at Wellingborough Town on Thursday night, while Deeping Rangers won 2-1 at Harborough Town.
In a stormy game at the Dog and Duck, lowly Wellingborough went ahead from the penalty spot early on before Nightinale levelled matters.
But he and leading scorer Cotton soon saw red before the break – and although the Tulips battled well with nine men, Todd Sawko netted a late winner for the hosts.
The loss leaves Pat Rayment’s side four points behind second-placed St Ives wit just three games to play, leaving their promotion dream in tatters.
Elsewhere, second-half strikes from Davie Burton-Jones and Tom James earned Deeping a battling win at Harborough.
It leaves them a point behind fourth-placed Huntingdon Town with two games left.