Will Jacks smashed English cricket's third fastest T20 fifty - off 15 balls - as Surrey beat rivals Middlesex.
On a night when Lancashire made it two North Group wins from two and Yorkshire and Gloucestershire also made winning starts, Surrey's victory at Lord's in the London derby took top billing.
Their total of 223-7 was the highest in 17 years and 72 games of T20 combat at English cricket's headquarters.
Jacks paved the way with the fastest T20 fifty in England in 11 years.
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He was first out in the ninth over with the score on 95, having smashed 70 off 24 balls, including his first 50 off just 15 deliveries.
Yuvraj Singh (for India against England in Durban in 2007, including his famous six sixes off Stuart Broad) and Chris Gayle (for Melbourne Renegades at home to Adelaide Strikers in 2016) jointly hold the record for the fastest half-century in T20 cricket at just 12 balls.
But only two have ever been scored quicker in the English T20, by Marcus Trescothick (13 balls, for Somerset against Hampshire at Taunton in 2010) and Yorkshire wicketkeeper Gerard Brophy (14 balls, against Derbyshire in 2006).
It was all too much for Middlesex as Surrey also broke their own Lord's T20 record.
This new highest T20 score at Lord's surpassed the 218-5 the Brown Caps got at the ground in 2020, which matched their 218-7 in 2006.
Jacks hit five sixes and nine fours, supported by a comparatively restrained 45 from 42 balls by England World Cup-winning opener Jason Roy.
Once Paul Stirling was run out for 58 out of 87 by Tom Curran in the ninth over, it was an uphill battle for Middlesex.
Jordan Clark got the key wicket of England one-day captain Eoin Morgan, who fell for 32, and Sam Curran took 4-29 as Middlesex ended well short on 169-9 to lose by 54 runs.
In the evening's other South Group game, Marnus Labuschagne was so nearly the Glamorgan hero as they lost by just four runs to Gloucestershire in Cardiff.
South Africa's Glenn Phillips top-scored with 44 as the visitors reached 179-6.
Australia Test and ODI international Labuschagne then kept his side in it with 10 fours and two sixes in his unbeaten 93 off 56 balls - but, despite a brave unbroken last-wicket stand with Prem Sisodiya, they fell just short.
Lancashire off and running
Lancashire Lightning are going great guns in the County Championship this season - or at least they were until they lost to Labuschagne and Glamorgan last week.
And they have also started well in the T20. The Lightning made it two home wins in successive nights as they disposed of Leicestershire Foxes by 15 runs to follow up Wednesday's six-wicket win over Derbyshire.
New Zealand international Finn Allen thumped an unbeaten 73 off 51 balls as the hosts posted 172-8 - a run more than they had managed against Derbyshire.
And, despite 54 not out from opener Scott Steel, plus cameos from Josh Inglis (34 off 19) and Rishi Patel (32 off 17), the Foxes' victory bid ran out of steam.
Yorkshire Vikings also got their campaign off to a winning start with a comfortable six-wicket victory over Birmingham Bears in Leeds.
Jordan Thompson (3-23), Matthew Waite (2-36) and David Willey (2-27) were all in the wickets as the Bears were restricted to 144-8.
Sam Hain was their best batter with 59, well supported by former Yorkshire and England all-rounder Tim Bresnan (23).
Jonny Bairstow then top-scored for the Vikings with 34 off 22 balls, sharing 59 for the second wicket with England colleague Dawid Malan, as the hosts won on 147-4 with nine balls to spare.
What's up next?
Durham v Yorkshire (Chester-le-Street, 18:30 BST)
Leicestershire v Derbyshire(Leicester, 18:30 BST)
Northants v Worcestershire (Northampton, 19:00 BST)
Notts v Birmingham Bears (Trent Bridge, 18:30 BST)
Essex v Hampshire (Chelmsford, 19:00 BST)
Gloucestershire v Sussex (Bristol, 18:30 BST)
Kent v Middlesex (Canterbury, 19:00 BST)
Somerset v Surrey (Taunton, 18:30 BST)