Hopes of a return to Wembley were ended yesterday when Warrington clinically swept them aside in the double-header at University of Bolton Stadium.
Wolves will now play Catalans Dragons in the final on August 25 after the French club stunned Super League leaders St Helens 35-16.
However, struggling Rhinos must immediately turn their attention to securing their top-flight status with another French side – Championship Toulouse Olympique – arriving for the Qualifiers opener at Emerald Headingley on Saturday.
With just one win in their last nine outings, and given the manner of yesterday’s defeat, there are mounting concerns that Leeds could be in real danger of relegation.
Sinfield said: “I don’t feel like we have any momentum behind us at this moment in time so we’ve got to move quickly. I wouldn’t say it’s worrying – that’s probably the wrong word. But I think it’s a concern.
“There’s obviously some teams that are going to come after us and rightly so – I don’t blame them.
“We’ve got to be ready for that fight and that challenge. We start a new comp’ tomorrow morning (Monday).
“I think there’s some realisation that this is where we’re at so we’ve got to do something about it.”
Leeds took an early 6-2 lead through Ryan Hall’s try but were 26-6 down by the break and never truly looked like clawing it back.
But Sinfield refused to blame his players who had been asked for a response after a woeful defeat to 12-man Salford Red Devils the week before. “I’m not going after the players here,” he said.
“I don’t think that’s fair. We’re all in it together and so we’re all responsible.
“I thought our response for first 15 minutes after half-time was Leeds-like, somewhere where we need to be.
“But other than that it was an ugly day.”
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