London Broncos moved back into the top four at the expense of Halifax following a 20-18 win.
The Broncos went 14-0 ahead early in the second-half, before Halifax scored twice through Kieren Moss and Shane Grady.
But Ben Evans’ try soon after restored the eight point lead, and although former Broncos forward Jacob Fairbank scored late on, London held on.
It means Halifax have dropped out of the four and will need to beat Toulouse and Rochdale in the final two games to secure their passage into the Qualifiers.
Toulouse and Featherstone are also in the four after comfortable wins over Barrow and Swinton respectively.
The French outfit defeated Barrow 72-6, while Featherstone beat Swinton 60-4.
Next week sees two pivotal games take place, with Halifax hosting Toulouse and Featherstone taking on London.
Leigh, who defeated Rochdale on Saturday, also remain in the mix but need results to go their way.
Extensive reports will be in League Express on Monday.