Steven Finn starred with another impressive bowling display to secure a resounding derby victory for Middlesex against London rivals Surrey at Lord’s.

The England seamer returned figures of 3-17, while Neil Dexter took 3-12 as Middlesex triumphed by 43 runs to leave Surrey’s hopes of qualification for the NatWest T20 Blast quarter-finals hanging by a thread.

They will have to beat Sussex at The Oval on Friday and rely on other results going in their favour – while Middlesex, who were already out of contention, finish their campaign against Somerset at Taunton.

Middlesex, who won the toss and decided to bat, lost Nick Gubbins (6) early on as he flicked Jade Dernbach for six and then played on two balls later.

His replacement John Simpson flourished in a second-wicket partnership of 73 with Dawid Malan, dominating the strike and smashing a string of boundaries, which included all of Tom Curran’s first three deliveries through the off side.

But Surrey captain Gareth Batty, bowling in tandem with fellow spinner Zafar Ansari, significantly slowed the scoring rate and the latter picked up the wicket of Malan (23), well caught at long-on in the 10th over.

Simpson soon followed for 53, with Ansari taking a catch on the deep-square boundary, but Eoin Morgan and James Franklin rebuilt the home side’s innings with a stand of 77.

The pair began to accelerate in the last three overs, with Franklin – whose 41 came from just 21 balls – hitting Tom Curran for four boundaries in a row and Morgan (48) heaving successive sixes off Dernbach.

Both batsmen eventually holed out as Middlesex posted 185-5 – and, like their opponents, Surrey lost a wicket in the first over of their reply, with Jason Roy (5) caught at short fine-leg.

Mitch McClenaghan (2-36) picked up the wickets of Steven Davies (6), caught on the boundary and Rory Burns (1), who dabbed one to mid-off – sandwiching a superb diving catch by Malan to dismiss Ben Foakes (6).

That left Surrey in deep trouble at 33-4 – and their hopes of wresting back the advantage lay with Kumar Sangakkara, who seemed to be getting into his stride as he reached 32 from 25 balls.

But the Sri Lankan swung Dexter to long-off and Surrey continued to lose wickets at regular intervals, with Azhar Mahmood (2) and Ansari (17) both falling to catches by Ollie Rayner.

McClenaghan dived full length to remove Tom Curran (18) and Dexter bowled Batty (3), with Sam Curran (17 not out) and Dernbach (16no) ensuring that Surrey survived their full 20 overs to finish on 142-9.