Sussex 320 for 5 (Tear 73, Leaning 59*, Carson 53) beat Essex 316 for 6 (Thain 102, Westley 81) by five wickets
The Sussex Sharks won their first Metro Bank One Day Cup match at the fourth attempt, beating Essex by five wickets with just four balls to spare at Arundel.
Leaning struck just two fours in reaching fifty but hit a six in the penultimate over to set up victory.
That brought in Joe Johnson for his first team debut. And he lofted Mitchell Killeen over mid-on for six as 16 came off the over.
He and Tear added 46 runs from 45 balls before Johnson top-edged a sweep off Matt Critchley. And wrist-spinner Critchley struck again in his next over when Tear chipped a delivery straight back to him. He had hit seven fours and two sixes in his 72-ball 73.
Dan Ibraham maintained the momentum with 26 off 28 balls but it was a 99-run partnership between Leaning and the more attacking Carson that set up the win before some late blows from Fynn Hudson-Prentice.
The Essex innings was built around a second wicket stand of 151 in 24 overs between Thain (102) and Tom Westley (81). But Essex might have expected an even bigger total when they were 152 for one at the halfway stage of their innings.
The runs came more easily when the ball was hard and the Sussex bowlers were bowling more boundary balls.
Sussex broke through in only the second over when Hudson-Prentice had Luc Benkenstein, driving, caught by Jack Leaning at second slip. But that was the only joy for some time for a crowd of over 4,000.
But Thain should have gone when he had made only three, when he edged the returning Ollie Robinson to Leaning, although it was a more difficult chance than his first.
Instead Thain went on to make his first century for Essex at senior level, his runs coming off 116 deliveries and including 13 fours.
Westley, who scored a century in his only previous outing in the competition this season, was literally the driving force as 65 came off the first ten overs, with a dozen fours, with the hundred coming up in the 18th.
Westley, whose 81 came from 71 deliveries with 12 fours and a six, was second out in the 26th over when he pulled spinner Troy Henry to Ibrahim at short midwicket.
After that the main contribution came from Critchley (a run a ball 64) as the Sussex bowlers – and there were eight of them – cleverly mixed up their bowling and pulled back the scoring rate. Seamer Toby Munt was typical of that, his first two overs going for 28 but his seven going for 55.
