Essex 337 for 7 (Bopara 125, Lawrence 115) beat Kent 184 (Dickson 51, Porter 4-37) by 153 runs
Bopara's 125 took 88 balls and included 11 fours and six sixes, while Lawrence, surpassing his previous highest List A score by 79 runs, finished on 115 from 109 balls with seven fours and three sixes.
The pair put on 187 in 25 overs for the fourth wicket. It was a partnership that took time to ignite, principally because Darren Stevens bowled his allocated 10 overs straight through, taking 1 for 37, during which time Essex crawled from 45 for 2 to 132 for 3. The fireworks came a little later with the Eagles adding 167 from the last 15 overs, courtesy of their two centurions.
The unfortunate Calum Haggett bore the brunt of the second-half assault, conceding 90 runs for the consolation of two wickets.
Kent had won five games in a row to qualify for the knockout stages, but defeat at Chelmsford enabled Essex to climb above them on run-rate. They were always off the pace in their chase and suffered the ignominy of former player Matt Coles taking two key wickets, including Kent captain Sam Billings to the first ball he bowled. Jamie Porter claimed four wickets for the second consecutive match.
Lawrence and Bopara grafted to their first fifty partnership from 10 overs, with Lawrence passing his top List A score of 37 at the same time. It marked the point that the shackles came off. Lawrence hit Henry for a straight six to reach his half-century. He then posted the 100 stand from 17 overs with the first of successive straight sixes off Denly. Essex, accelerating, had added 55 in six overs.
A lofted sweep for his sixth four brought up Bopara's fifth fifty in the Royal London Cup this summer. It had taken 57 balls. Lawrence turned Haggett into the onside for the single that took him to a 99-ball century, his second fifty taking 42 balls.
The 150 partnership came up in 23 overs, followed by a mighty pull for six by Bopara. However, Lawrence went for one big hit too many and found Heino Kuhn at deep extra cover.
Ten Doeschate went in similar fashion, miscuing Haggett before Bopara hit the bowler for successive sixes over long-off and long-on. His century, reached with a push into the legside, came from 80 balls.
The New Zealander Henry, having taken two for 59 from 9.1 overs, was withdrawn from the attack after bowling his second waist-high full-toss. Haggett took over and Bopara smashed successive sixes, one straight and out of the ground, the other beating Qayyum on the rope.
Zaidi went to Sean Dickson's catch on the boundary before another six, from a full-toss by Claydon, prefaced Bopara's departure, caught in the deep by Kuhn. As a postscript, Coles's first ball against his old team-mates also cleared the ropes.
And when Coles dismissed Billings with his first ball, castled for six to reduce the Spitfires to 42 for 3 after 13 overs, his joy knew no bounds.
Kent had already lost Kuhn, after centuries in his previous two innings, for just four as Jamie Porter clipped the top of off-stump. Daniel Bell-Drummond hung around for 10 unproductive overs before swishing wildly at Sam Cook and was caught behind for 12.
Coles's second wicket was equally important in the context of the match as he had Denly caught at deep cover by Lawrence. Blake pulled Coles and drove Bopara for sixes, but played over one from ten Doeschate and was bowled for 41.
Dickson took 64 balls to make it to his fifty but perished on 51 when he lifted the returning Porter to Bopara at mid-off. Essex were heading for a home quarter-final.