The right hander – who was only playing because of an injury to Chris Dent  – came in with his side still needing 56 to win in 5.2 overs. But he took them to victory in style with a fearless display of powerful hitting that included four sixes and two fours.

Two of those maximums came in the 19th over – bowled by Toby Roland-Jones – which left 10 to win from the final over. Finn contributed to his side’s downfall with a no ball, a four and another no ball before the upper cut for six that won the game.

Gloucestershire will now face Durham Jets in the Quarter-Final at the Brightside County Ground on Wednesday , August 10th (6.30pm) – click here to buy your tickets online

Watch the winning runs below courtesy of My Action Replay:

Earlier Glos lost the toss and allowed Middlesex to get off to a quick start with some uncharacteristically ill-disciplined bowling.

Nick Gubbins (29 0ff 15) was the main man to capitalise, putting on 52 with Stevie Eskinazi (29) before skying Andrew Tye’s first ball to wicketkeeper Phil Mustard, who was making his home debut.

The experienced Durham loanee made his class tell moments later when he stumped James Franklin for 5 off Benny Howell to make it 65-2 in the 8th. The New Zealander was the first of three victims for Howell (3-18) who finished the NatWest Blast group stages as the top wicket taker in the country. He delivered a double wicket-maiden in the 10th over to swing the momentum back Gloucestershire’s way and leave the visitors on 68-4 at the halfway stage.

Tom Smith went wicketless but was also impressive through the middle period, finishing with 0-22 from four.

Having taken a while to get going John Simpson (40 not out), Ryan Higgins (24) took the attack back to Glos late on. And with Roland-Jones (18 not out) joining in with the fun in the final over – bowled by Tye (2-42) – Middlesex finished on 157-5.

In reply Hamish Marshall (16) ensured his side got out of the blocks quickly before being run out by Roland-Jones in the third over with the score on 31.

Michael Klinger – who finished as the group stage top scorer failed to get going and survived one dropped catch before being caught by Finn at short third man trying to switch-hit Nathan Sowter (1-17).

When Mustard was bowled by Franklin (1-9) Glos were on 80-3 after 11. But with the competition’s second highest scorer, Ian Cockbain continuing his impressive form there was no need to panic.

In the fourteenth over Roland-Jones removed both Cockbain (42) and Howell (9) to leave Glos facing an uphill task.

But as the destructive Taylor moved up through the gears Glos eventually reached their target with three balls to spare.