Middlesex needed just 80 minutes to wrap up a 10-wicket win and condemn Sussex to their first defeat of the season in the LV= County Championship.
Luke Wright was last out for 161 as Sussex were dismissed for 310 in their second innings before Middlesex’s openers knocked off a modest target of 44 in nine overs at the BrightonandHoveJobs.com County Ground.
Sussex had already lost the leadership of Division One to Yorkshire, who beat Derbyshire on Friday, and a congested top of the table now sees less than 20 points covering the top four, victory having lifted Middlesex into third place.
The hosts led by just 21 runs overnight with Wright on 151 but Middlesex made inroads as soon as they took the second new ball.
Tim Murtagh's first delivery with it made the breakthrough when Chris Jordan edged a lifter to wicketkeeper John Simpson.
Sussex lost their eighth wicket in the next over when Steve Magoffin wafted outside off stump and Simpson again did the honours to reward Corey Collymore's excellent line.
James Anyon briefly gave Wright some support, but Murtagh struck again with the score on 308 when Anyon was caught behind off another ball which lifted sharply off a length to give Simpson his eighth catch of the game.
With only last man Monty Panesar for company, Wright tried to hit out but succeeded only in finding Neil Dexter on the long-off boundary, having added 10 runs to his overnight score. Wright's defiant 185-ball innings contained 24 fours and a six.
Middlesex’s fourth win of the season was completed by Dawid Malan and Sam Robson, the latter’s first-innings 166 having done so much to set up the visitors’ triumph.
Robson’s first-class run-tally for the summer now stands at a healthy 986.