Paul Stirling and Dawid Malan shared a record opening partnership for Middlesex in limited-overs cricket as Leicestershire were put to the sword in the Yorkshire Bank 40 at Grace Road.
Stirling, dropped before he had scored, hit a superb unbeaten 132 off 96 balls as he shared an unbeaten opening stand of 221 with Malan to inflict a crushing 10-wicket win.
The Foxes, who lost their 100 per cent record in this year's competition with the defeat, were bowled out for 220 before Middlesex raced to victory with 9.4 overs to spare.
Stirling, who was put down at slip by Greg Smith off Anthony Ireland in the second over, reached 50 off 29 deliveries and his century came up off 71 balls.
He struck the winning runs with his 19th boundary and Malan gave him great support in a chanceless knock, finishing on 80 not out off 86 balls with a six and seven fours.
Their record partnership - which beat the previous best of 218 against Gloucestershire last season between Malan and Chris Rogers - saw Middlesex record their second win in five matches, while the Foxes suffered their first defeat in four games.
Earlier, it was a disappointing batting performance from Leicestershire, with several players getting starts without going on to make a telling score.
Yet they looked on course to post a competitive total when they were 102-1 in the 16th over. Then five wickets fell for 36 runs in 11 overs, and from that point on it was an uphill battle for the hosts.
Josh Cobb, having scored three consecutive centuries in the competition, hit the first ball of the match to the boundary and made 25 in an opening partnership of 51 with Niall O'Brien, before being bowled by James Harris.
O'Brien and Smith also shared a second-wicket stand of 51 with the latter hitting a massive straight six off Tim Murtagh. But when Smith was caught behind by wicketkeeper Adam Rossington off Murtagh for 30, his departure triggered a collapse.
O'Brien was caught at point for 41 off 46 balls, Joe Burns edged to slip without scoring while Shiv Thakor and Matt Boyce were both snared by off-spinner Ollie Rayner as the Foxes slipped to 138-6.
Michael Thornely, with 39 off 40 balls, helped to rebuild the innings and take the total past 200, but Jigar Naik was last man out with one ball left.