Yorkshire boosted their promotion hopes with only their second win in the last seven games against Twenty20 cup winners Leicestershire under the Grace Road lights.
After posting 177 for eight off 32 overs in their rain interrupted innings Yorkshire dismissed the home side for 145 to win by 34 runs under the Duckworth-Lewis method.
It was a massive anti-climax for the Foxes, who had paraded the Twenty20 cup around the ground during the interval.
But this was their third consecutive defeat in the totesport league since they lifted the trophy at Edgbaston 11 days ago.
It was a match both sides desperately needed to win and the loss virtually ends Leicestershire's hopes of promotion from Division Two.
But Yorkshire are right back in the thick of things again with Australians Darren Lehmann and Ian Harvey at the heart of their solid batting performance.
Harvey hit a typically belligerent 37 off 30 balls in an opening stand of 56 with Matthew Wood.
And then when Yorkshire looked to be heading for trouble at 75 for three Lehmann took control, scoring a carefully crafted 56 off 61 balls.
He and Anthony McGrath put on 68 in 12 overs for the fourth wicket and from there the visitors were able to reach a highly competitive total.
Under the lights it was certainly too much for Leicestershire, with only four of their batsmen reaching double figures.
In fact, the extras total of 28 was the biggest contributor to the home side's innings and the best stand was 30 for the last wicket between Charles Dagnall and Mark Cleary - who had to bat with a runner after twisting his ankle while bowling.
Paul Nixon top-scored with a modest 25 as Yorkshire's bowlers turned the screw with off-spinner Richard Dawson emerging with impressive figures of three for 20 in his seven overs.
Harvey completed a good all-round performance by taking 2-27and McGrath also picked up two wickets as Leicestershire were dismissed with nine balls of their innings remaining.