Sussex 262 (Hudson-Prentice 65, Salisbury 5-73) and 344 for 9 dec (Coles 63, Scriven 4-55) beat Leicestershire 108 (Patel 48, Karvelas 4-14) and 483 (Ackermann 136, Amin 94, Scriven 78, Cox 58, Unadkat 6-94) by 15 runs
Indian left-armer Jaydev Unadkat took six wickets on his home debut as Sussex revived their promotion challenge by wearing down Leicestershire's spirited resistance to claim only their second win of the season in the LV= Insurance County Championship.
Undakat defied the discomfort of a sore ankle to take an outstanding 6 for 94 from 32.4 overs including the last four wickets in 31 balls as they bowled out the Foxes for 483 at Hove to squeeze home by 15 runs.
Sussex visit Derbyshire next week before finishing the season at home to Gloucestershire but second-placed Worcestershire, who currently have a 18-point advantage over Sussex, are still favourites for the other promotion place. They play Durham at New Road next week before finishing at Headingley.
After Ackermann and Amin put on 180 for the fourth wicket, Scriven and Ben Cox added 130 for the seventh to take Leicestershire to within 46 runs of victory when Undakat produced an inspired spell down the slope.
He found some bounce and seam movement on a benign surface to defeat both established batters. Having made his career-best, Scriven was drawn half-forward and edged behind and Cox taken at head height at slip by Tom Alsop before Scott Currie nibbled at a full-length delivery to bag a second-ball duck.
That left Chris Wright, who joins Sussex next season, and last man Matt Salisbury needing 43 and Salisbury batting with a runner because of a hamstring injury. Wright had famously guided Leicestershire to a target of 389 against Yorkshire earlier in the season and when he slapped Fynn Hudson-Prentice for two sixes to help get the target down to 16 Sussex nerves were jangling again, only for Unadkat to produce a brilliant leg-stump yorker that was too good for Wright.
Leicestershire had the consolation of making the highest fourth-innings total in their history and there were plenty of periods during a fluctuating day when they looked favourites.
Ackermann and Amin added 67 runs in the first hour with few alarms but with the new ball an over away, off-spinner Jack Carson removed both batters in the space of four deliveries. Ackermann, who'd hit 21 fours, was bowled making room to cut and Amin played for turn which wasn't there and was struck on the back pad six short of his hundred, having hit 17 boundaries.
Rehman Ahmed threatened to make the most of being dropped at short leg by Alsop with a single to his name, moving quickly to 29. Sussex had delayed taking the new ball for ten overs but in his third over with it Unadkat persuaded Ahmed to drive at a ball well outside off stump and Carter took a good catch diving to his right.
However, with the pitch showing little sign of deterioration Scriven and Cox settled in, saw off the threat of the new ball and after lunch began to tick off the runs with few alarms.
Umpires Ben Debenham and Paul Baldwin had to speak to both Carson and captain Cheteshwar Pujara as Sussex's frustrations threatened to boil over, before Undakat changed the mood completely and the hosts could celebrate winning more than one game in a Championship season for the first time since 2019.
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