Rossington's 50-ball 95, with 10 fours and five sixes, was the stand-out performance in the Essex total of 197 for 8. It was his highest score in the competition
Hove: Essex Eagles 197-8, Sussex Sharks 169-8 - Essex Eagles won by 28 runs
A magnificently miserly bowling stint from the Essex Eagles captain Simon Harmer led his side to victory at Hove.
Harmer conceded just 18 runs from his four overs and also picked up the wickets of danger man Ali Orr, Tom Alsop and George Garton. It was the eighth win of the campaign for Essex as Sussex disappointed once again before a sell-out crowd.
But Orr, the hero of Sussex's first County Championship win of the season two days before, threatened more heroics as Sussex chased a challenging 198 for victory.
Sussex took just five runs from Aaron Beard's first over but then Orr plundered 25 runs off the second over, bowled by Daniel Sams.
Rashid Khan returned figures of 3 for 30 for Sussex Sharks [Getty Images]
After just four overs Sussex were 54 without loss, with Orr flying on 36. Josh Philippe was caught behind for 17 in the fifth over but after seven overs Sussex were better than on target, at 81 for 1. But then Orr's fine knock came to an end as he skied Harmer to midwicket. His 41 had come off just 21 balls.
Sussex were ahead of the game at the halfway stage, at 101 for 2, but Harrison Ward holed out to the deep midwicket boundary for a 22-ball 31 and a brave 28-ball 47 from Sussex captain and former Essex man Ravi Bopara was not enough.
Earlier, Adam Rossington's 50-ball 95, with 10 fours and five sixes, was the stand-out performance in the Essex total of 197 for 8. It was his highest score in the competition, but when Essex were 68 without loss in the seventh over they must have fancied their chances of scoring even more after being invited to bat.
Rossington brought up the fifty in the sixth over as he drove Henry Crocombe for a straight four, the bowler's first three deliveries going for boundaries.
Michael Pepper is bowled [Getty Images]
Sussex battled their way back into the match by taking three wickets in the space of 10 deliveries. Delray Rawlins bowled Robin Das; Michael Pepper, reverse sweeping, was brilliantly caught by Ali Orr diving to his right at backward-point; and Dan Lawrence was bowled by Bopara's second ball.
Rossington moved to 95 with a six over long-off but was stumped next ball and it was Essex's red-ball captain Tom Westley, with a 30-ball 54, who was responsible for ensuring his side reached a challenging total.
Westley struck three fours and four sixes, hitting Garton out of the ground over the hospitality area at cow corner. Rashid Khan was once again the best Sussex bowler with 3 for 30 runs while Bopara (2-30) and Rawlins (2-34) also bowled well.
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