The Champions became the second high-profile casualties in 24 hours of a Super League that genuinely has become wildly unpredictable.
Leeds stood to go level on points with third-placed Wigan if they could beat a depleted Humberside line-up, but they were defied by a performance every bit as gutsy as Widnes’ at Warrington the previous night.
With their record of winning Super League titles from further down the table, Leeds cannot be expected to be unduly stressed about whether they finish third or fourth this time. It is much more a question of what their current form is like going into the play-offs and the signs at Headingley last night were very mixed.
Rovers, with a play-off place of their own to hang on to, but 10 first-teamers missing, made life fiendishly difficult in a first half which ended with them deservedly in front.
Some magnificent defending then enabled them to stay in the lead despite a late Leeds surge.
It took the Rhinos 19 minutes to make their breakthrough, with perhaps the best of this year’s new crop, Liam Sutcliffe, making the burst that set up Kallum Watkins. Rovers hit back swiftly, Leeds failing to deal with a typical Michael Dobson kick for the corner and Jordan Cox latching on to it to score.
A minute from the break, a bullocking run down the left from the big forward, Rhys Lovegrove, put the Robins ahead and comparisons with Widnes’ winning performance at Warrington were becoming irresistible.
They stretched their improbable lead with a Dobson penalty after the interval, but Leeds built pressure inexorably until it seemed that they must score.
Instead, they turned the heat back on the Rhinos with another penalty from the immaculate Dobson. Ryan Hall went desperately close from Kevin Sinfield’s kick, but the Robins held on, despite near-exhaustion, with the sort of determination that wins impossible victories.
Seven minutes from time, however, great work from the young winger, James Duckworth, put Watkins over for his second. That guaranteed a nerve-wracking last few plays, but the Robins deserved to hang on to win. Also last night Hull beat Salford 18-13.
Leeds: Jones-Bishop, Duckworth, Watkins, Hardaker, Hall, Sinfield, Burrow, Leuluai, McShane, Peacock, Ablett, Clarkson, Sutcliffe. Substitutes used: Foster, Moore, Kirke, Singleton.
Hull K R: Hall, D Hodgson, Salter, Gleeson, Caro, Burns, Dobson, Tuimavave, J. Hodgson, Walker, Lovegrove, Cox, Mika. Substitutes used: Withers, Netherton, Ollett, Green.
Referee: R Silverwood.