Mohammad Amir took 4 for 29 as Essex edged Sussex by nine runs in Vitality T20 Blast.
Amir, who recently returned with figures of 6 for 64 in a first-class game against Kent, bowled 12 dot balls in his quota of four overs.
Put in to bat first, Essex scored 168 from their 20 overs, with notable contributions from Dan Lawrence (59 off 43) and Ravi Bopara (45 off 24). Reece Topley and Will Beer returned with two wickets each.
Sussex, in reply, lost their openers Phil Salt and Luke Wright in quick succession. Both batters were removed by Mohammad Amir.
David Wiese was the only batsman to provide solid resistance to Essex with a breezy 66 off 37 balls.
Amir then returned to clean up the lower order as Sussex were reduced to 159 from 20 overs.
Sussex currently stand on top of the table in the South Group with 15 points to their name.