Surrey and Somerset suffered shock defeats to Sussex and Hampshire respectively during an entertaining evening in the Vitality Blast.

The Sharks’ five-match losing streak came to an end with Thursday’s 17-run win at Hove as the South Group leaders lost for the first time in this season’s competition.

Opener Will Jacks looked to be leading Surrey to a target of 173 when he took his aggregate in this season’s competition to 396 runs with 76 – his fifth fifty of the campaign.

But when he was caught behind trying to guide a quicker ball from left-arm spinner Delray Rawlins into the off side in the 15th over, having hit 11 fours and a six, Surrey’s lower order folded quickly and they were bowled out for155 in 18.2 overs – their first defeat in any competition this season.

There was a dramatic evening in Taunton, where James Vince scored Hampshire’s highest individual score in T20 cricket in a 16-run win against second-placed South Group side Somerset.

The Hawks skipper smashed 129 not out off just 62 balls, with 10 sixes and nine fours, and was well supported by 19-year-old Tom Prest (62) as Hampshire recorded their biggest total in the competition, 208 for five, after losing the toss.

After a brief stoppage for rain, Somerset replied with 194 for nine, Rilee Rossouw top-scoring with 55 off 28 balls and Tom Banton contributing 54 from 38 deliveries. Chris Wood claimed two for 26.

Elsewhere, Sam Cook’s stunning triple-wicket maiden helped keep Essex in the hunt for a Vitality Blast quarter-final berth as they beat Middlesex by 21 runs at Lord’s.

Seamer Cook ripped the heart out of Middlesex’s top order with the wickets of Max Holden, Joe Cracknell and wicketkeeper John Simpson en route to figures of three for 23.

That left the hosts on nine for three, needing 162 for victory, and although captain Steve Eskinazi (43) and Jack Davies (41) mounted a recovery with a fourth-wicket stand worth 86, the hosts were limited to 140 for eight.

In the North Group, leaders Lancashire’s game against Durham was abandoned due to rain in Blackpool.

Stand-in skipper Steven Croft made his second successive fifty at his home club but may have been a shade relieved as the Lightning were moderately placed on 133 for six after 17.4 overs when the rain arrived at 6.30pm.

The result means that Lancashire need only to beat Derbyshire on Friday to clinch their qualification for the knockout phase.

Ben Duckett had a good evening for the Outlaws
Ben Duckett had a good evening for the Outlaws (Simon Marper/PA)

The Falcons head into that game nursing their wounds after their five-match winning streak came to an abrupt halt against Nottingham.

The Outlaws had suffered three consecutive defeats before their unerring 94-run victory, posting 247 for six on their way to the win – their highest total in the format.

Ben Duckett hit a season’s-best 63 and Alex Hales his third half-century of the campaign as the Outlaws, who conceded a competition-record 261 against Birmingham last week, enjoyed their best night of what has been a disappointing season.

Meanwhile, Yorkshire kept qualification in their own hands as they beat bottom-placed Worcestershire by five wickets.

England spinner Dom Bess destroyed the Rapids’ middle order on his way to career-best T20 figures of three for 15 from his four overs after the home side were put in to bat.

Worcestershire newcomer, Kashif Ali, and keeper Gareth Roderick added an unbroken 73 to enable the Rapids to set a 151 target on a green pitch.

But an unbeaten 46 from ex-Worcestershire player Tom Kohler-Cadmore saw his side home with 5.2 overs to spare.