A superb run chase from Leicestershire took them 3rd in the Vitality Blast North Group, as they edged out Yorkshire by three wickets from the final ball.
Put in after losing the toss, Yorkshire made a promising start by reaching 28 after 3 overs but they then lost Tom Kohler-Cadmore, caught by Ben Mike off Will Davis, for 3.
Adam Lyth dominated the remainder of the powerplay, reaching his half century in just 24 balls, as the Vikings made 63-1 from the first six overs.
Lyth and David Willey took the score to 98, before the latter was bowled by Davis for 27 off the final ball of the 10th over.
Lyth would fall for 71 from 46 balls in the 13th, holing out off Gareth Delany at 110-3. Will Fraine’s stay was not a long one, as he was run out by Ackermann without scoring.
Leicestershire continued to drag their way back into the game, with Delany picking up a second wicket to remove Harry Brook caught by Taylor for 15.
Jordan Thompson put an end to the Foxes revival with four sixes in eight balls. He ended with 44 from 19 balls and was dismissed off the final ball of the innings. Yorkshire ended with 188-6.
The Yorkshire seamers made a good start to their defence and kept things tight, before Dearden ran out of patience and was caught on the boundary for 7 in the fourth over.
Arron Lilley hit two big sixes to boost the Leicestershire score, as they made 47-1 from the six overs of powerplay.
Lilley’s cameo was ended by a full toss from Jack Shutt, the former Lancashire man caught for 30 from 14 balls.
Irish international Gareth Delany and Foxes captain Colin Ackermann then combined to give the home side their first sniff of victory. Delany hit three sixes to bring up a 50 in 32 balls on his home debut.
The 14th over disappeared for 28, Delany and Ackermann tucking into the bowling of Thompson.
Yorkshire turned to David Willey to break the partnership, and he obliged removing Delany for 64.
Tom Taylor was out LBW first ball, but Ackermann moved to his 50 from just 29 balls with 31 needed from the last 4 overs.
Lewis Hill was caught at mid off for 2, before a superb catch from Ben Coad gave Matthew Fisherhis third wicket as Harry Swindells went for 0.
That brought Ben Mike to the wicket and he launched an enormous six to keep the Foxes in the contest, but they lost Ackermann LBW to Willey for 58. They were left with 9 required off the last over.
Lyth was the surprising choice to bowl and, with three needed off the final ball, Mike smashed another six to end 22 not out from 9 balls. Leicestershire won by three wickets off the final ball.