Middlesex batsman Stevie Eskinazi hit 130 off 101 balls on his return from injury to help beat Worcestershire by 13 runs at New Road in the One-Day Cup.
The right-hander now has a three-figure score in all three formats of the county game this season.
Middlesex totalled 302-5 in 41 overs in a rain-reduced match and Worcestershire could only reach 289-7.
Elsewhere, there were wins for Essex, Somerset, Lancashire, Gloucestershire, Nottinghamshire and Northamptonshire.
It was Middlesex’s first One-Day Cup win of the season, and Eskinazi has now scored a combined total of 889 runs in the County Championship, T20 Blast and One-Day Cup.
He put on 129 with Sam Robson (57), and although Brett D’Oliveira (74), Tom Fell and Jake Libby (both 58) did their bit for the home side, they had too much to do in the closing overs.
New leaders in both groups
With Group Two pacesetters Surrey and Glamorgan not involved in Sunday’s matches, Somerset had the opportunity to go top, and they did not waste it as James Hildreth’s unbeaten 61 off 34 balls led them to a five-wicket win over Yorkshire at Taunton.
It was the last match to start at 15:30 BST, leaving only 20 overs a side possible, and Yorkshire were carried to a score of 158-5 by Matthew Revis (58 not out off 41 balls) and William Luxton (31 not out) – aged 19 and 18 respectively – who shared an unbroken 69-run stand.
It was not enough, though, as Hildreth used all his experience to hit four sixes and five fours and help Somerset seal the win with five balls to spare.
There was a low-scoring Group One contest at the Ageas Bowl, with Lancashire beating Hampshire by 51 runs via the DLS method to move above Worcestershire at the top of the table.
Tom Bailey and George Balderson took three wickets each as Hampshire were bowled out for 162 and Lancashire had reached 115-2 in the 26th over, with Luke Wells 66 not out from 62 balls, when rain ended the game.
Two first-time winners – but Sussex miss out
Prior to Sunday’s matches, there were five teams, including Middlesex, who had yet to register a One-Day Cup win.
Two of them, Northants and Derbyshire, met at Wantage Road, but the game had to be reduced to 28 overs each after a delayed start because of morning rain showers.
Derbyshire made a horrendous start, with 17-year-old Mitch Wagstaff lbw to the first ball of the game, from Jack White (4-20), and three more batsmen were dismissed by Ben Sanderson in the next over to leave them 8-4.
Fynn Hudson-Prentice hit 64 off 43 balls – his third half-century in this season’s One-Day Cup – as the visitors recovered to reach 177-9, but Emiliano Gay and Ricardo Vasconcelos began the chase with an opening stand of 106.
Vasconcelos fell for 50, but Gay reached 84 not out before Rob Keogh (33 not out) hit a six to see them home on 183-2 with three balls remaining.
Sussex appeared on course to break their duck in Group One as they chased Gloucestershire’s 218-8 at Hove, but eventually lost out by three runs under the DLS method, required because of a 15-minute delay at the start.
Ben Brown, relieved of the captaincy last month, made 63 and Oli Carter hit three sixes in his 59 off 48 deliveries, but Jared Warner and Tom Smith claimed three wickets each as Sussex were all out for 214.
Cook maintains fine form
Essex are out of the running to retain the County Championship and Bob Willis Trophy titles they won in 2019 and 2020, and failed to qualify for the knockout stage of the T20 Blast.
The One-Day Cup, therefore, represents their sole remaining chance of silverware and they made short work of winless Kent at Chelmsford for their third victory in four games in Group One.
Kent’s largely youthful team – with the exception of Darren Stevens – were bowled out for 158 with the wickets shared between six Essex bowlers.
Matt Milnes bowled Will Buttleman in the seventh over of Essex’s reply, but it was plain sailing from that point on as Alastair Cook and Tom Westley shared an unbroken partnership of 127.
Cook followed his 92 not out against Middlesex two games previously with nine fours in his 77 not out, and Westley made an unbeaten 69 as the home side reached 159-1 in just 31.1 overs.
Nottinghamshire were equally convincing in Group Two as they moved up to second with a seven-wicket victory over Leicestershire, who were bowled out for 144 as Luke Fletcher took 4-30.
Peter Trego passed 5,000 List A runs in his 39 for Notts, who cruised home in just 20.2 overs on 145-3.
Tuesday, 3 August (play starts 11:00 BST)
Gloucestershire v Essex, Bristol
Lancashire v Middlesex, Old Trafford
Glamorgan v Surrey, Cardiff
Yorkshire v Warwickshire, York