Rhinos have won just one of their last seven games heading to Wheldon Road which has also rarely been a happy hunting ground for them in recent times.
They lost 18-12 against Hull FC on Sunday but dominated field position and Agar is not likely to make many changes tonight.
“We’re very much of the mind still we’re doing plenty right,” he said, having beaten Wakefield Trinity and fallen 14-13 at Huddersfield Giants previously.
“Defensively we had a very good performance with a couple of very costly individual errors.
“When you look at the way we dominated field position for long periods, we don’t think we have too much to fix up. Clearly we’ve had a lot of good ball the last two weeks and not posted enough points. We’ve got to take chances. We had them (Hull) exactly where we wanted but our pass selection/execution wasn’t right.”
Castleford’s fine start to the campaign has waned slightly with back-to-back defeats against Hull KR and Warrington Wolves.
But Liam Watts, Oli Holmes and Pete Mata’utia are all back in their squad tonight and Agar – who said Leeds securing England star George Williams was “unrealistic” – added: “They have key individuals.
“Paul McShane is very central to what they’ve done for a long time. And they know how to play the Jungle pitch very well.
“We see the threats coming from Paul and Jake Trueman.
“They’ll have their hands on the ball the majority of the time when Cas are attacking.”
Meanwhile, centre Harry Newman has had a “frustrating setback” in his recovery from a broken leg suffered last September
He hoped to return against St Helens on June 11 but a scan has revealed he will need at least another six weeks of healing.
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