Middlesex 203 for 6 (McCullum 63, Simpson 51, Lawrence 3-21) beat Essex 131 (Foster 50, Helm 5-11)
Brendon McCullum led from the front with an exhilarating 63 off 28 balls as Middlesex, who totalled 203 for 6, then dismissed Essex Eagles for 131 to win by 72 runs in front of a 27,000 sell-out crowd at a floodlit Lord's.
Middlesex captain McCullum smashed five sixes and six fours, was given fine support by a John Simpson half-century, and later - after Dan Lawrence had grabbed a T20-best 3 for 21 from his four overs - saw 26 runs plundered from the final over of the innings as Ryan Higgins, Tim Southee and James Franklin all hit the suffering Matt Dixon for sixes.
The win was a vital one for Middlesex, who before the game were level with Essex and two other counties on five points at the bottom of the NatWest T20 Blast's South Group but now move up into the middle of a tightly-packed table.
Adam Wheater fell in the first over of Essex's reply, spearing Southee to cover point, and soon Eoin Morgan had claimed four catches in that position as Varun Chopra, Lawrence and Ryan ten Doeschate all picked out England's one-day captain with lifted or mishit cuts.
Tom Helm, who ended with his and his county's T20-best of 5 for 11, earlier removed Chopra with his second ball, while Steven Finn got his revenge for being swatted for two sixes by Lawrence and for conceding 31 runs from his first two overs and added ten Doeschate's scalp for good measure.
By then Ravi Bopara had run himself out for 10, calling ten Doeschate for a single that wasn't there and failing to beat Simpson's throw to the bowler's end after being sent back, and when Ashar Zaidi skied George Scott's medium pace to backward point to go for 2 the chase was all but over at 62 for 6.
James Foster offered some defiance with 50 from 25 balls, but Helm returned to have him, Paul Walter and Mohammad Amir all caught slogging desperately in the 15th over and, in his following over, the 23-year-old fast bowler made it four wickets in six balls by bowling last man Dixon.
Middlesex were 54 for 1 after five overs, and then 110 for 2 off ten, as a result of McCullum's explosive innings, although wicketkeeper-batsman Simpson was not too far behind in terms of destructiveness as they added 73 in little more than six overs for the second wicket.
The game's opening over, bowled by Amir, contained just one run off the bat but, from then on, sixes and fours rained down on a capacity crowd as warm early evening sunshine also graced the occasion. To attract so many spectators to Lord's for this fixture, when England's third Test against South Africa had started across London at The Oval earlier in the day, said much both for Middlesex's marketing strategy and for the enduring popularity of the competition itself.
McCullum, put down on 0 by left-arm seamer Paul Walter when the New Zealander crunched his first ball back to him at the start of the second over - it was a difficult chance - immediately celebrated his let-off by driving through extra cover for four, slashing high to fine third man for another four and then swinging to long on for six as 16 came off the over.
Nick Gubbins went for 1, well held diving forward by Chopra as he came in from the deep square leg ropes off Dixon, but McCullum uppercut and forced Dixon and Walter for fours before flat-batting the latter over cover for his second six.
There were two more sixes pulled off successive balls from Amir in the fifth over, and McCullum's fifty soon arrived off just 19 balls. McCullum's fifth and final six was a slog-sweep off Bopara just before the same bowler had him held at long on later in that same ninth over.
By now, the left-handed Simpson was also into his stride, going into the 30s by pulling and lofting Bopara for fours and then swinging Simon Harmer's off spin for a beautifully-timed six over long on. His eventual 51 came off 39 balls, with two sixes and two fours.
Morgan contributed a useful 30-ball 39, which included sixes pulled off Amir and swept off left-arm spinner Zaidi, but he was bowled by Lawrence in the 18th over after the occasional off spinner had already slowed up Middlesex's advance by having Simpson stumped by Foster and then Scott caught behind for a duck in his previous over.
The innings, though, finished with a cricketing show of fireworks as Higgins swung Dixon over the deep square leg ropes before being bowled attempting something similar, Southee heaved his first ball over midwicket for six and Franklin flicked a ball aimed down the legside for another six before inside-edging a fortuitous four past keeper Foster as Middlesex made it past the 200 mark.
