A 26-12 defeat at home to Widnes Vikings leaves Whitehaven still almost safe – but not mathematically certain.
Neighbours Workington Town are now certain to be relegated and Haven lead Dewsbury by six points with four games to play.
It seems highly unlikely that the Rams will win those final four games but Haven would like to achieve safety through their own means.
They certainly gave a good account of themselves in defeat on a strength-sapping day because of the conditions.
They had clawed their way back to 14-12 early in the second half but it was the Vikings who finished the game strongly to score two more tries.
Not for the first time this season Haven did not make the best of starts and were 12-0 down in 16 minutes.
Matt Fleming and Sam Wilde crossed for tries which were both converted by Ste Tyrer.
Whitehaven responded gradually and on the half hour they reduced the arrears.
The home side worked a good move from a scrum and Will Evans crashed over for Nikau Williams to convert.
That was it for the first-half and soon after the resumption Tyrer took the two points on offer from a penalty.
But it was game on when Ryan King followed up his own grubber kick to touchdown and with Williams in the bin Josh Evans added the conversion.
Whitehaven, however, couldn’t manage to break through again and two tries in the final quarter from Liam Bent and Matty Fozard, both converted by Tyrer carried Widnes clear.