Joe Denly made 99 not out as Middlesex smashed Unicorns by nine wickets in the YB40.
Denly put on an unbeaten 168 with opener Dawid Malan as Angus Fraser's team dismantled the semi-professional side at Southend-on-Sea.
Malan made an unbeaten 58 from 80 balls while former-England international Denly hammered four sixes and eight fours in his 86-ball knock; it was Malan's fourth fifty in his last five YB40 innings as the duo chased down 170 with over ten overs to spare.
Tim Murtagh earlier took three wickets as Unicorns struggled to 170 all out in just 36.4 overs.
Middlesex are next in action on Friday against Kent at Canterbury in the first of their Twenty20 matches following a pre-t20 tour to Jersey.