Glamorgan 135 for 3 (Ingram 46*, Carlson 40) beat Middlesex 131 (Fuller 46*, Smith 4-6, van der Gugten 4-31) by seven wickets
Birthday boy Ruaidhri Smith recorded the best-ever economy rate by a Glamorgan bowler in T20 cricket as his side demolished Middlesex by seven wickets at Richmond.
Smith celebrated turning 24 with the remarkable figures of 4 for 6 from four overs as the home side were rolled over for just 131 - and slid to their eighth Vitality Blast defeat in nine games.
Glamorgan cantered past that modest target in only 12.5 overs to complete their third straight victory and strengthen their chances of qualifying for the quarter-finals.
Glamorgan elected to bowl first after winning the toss and that decision was proved resoundingly correct as Smith immediately blew away the hosts' top order.
Nick Gubbins was the first to go, neatly caught by Graham Wagg at short cover, and Stevie Eskinazi chopped on for a fifth-ball duck at the end of the same over.
Eoin Morgan also played on and, when Smith uprooted the off stump of Paul Stirling, Middlesex were already sinking fast at a wretched 20 for 4.
There was no sign of the carnage abating as Timm Van der Gugten removed James Franklin and Robbie White, both lbw in the space of three deliveries.
James Fuller led a mini-recovery, hitting Craig Meschede for three boundaries in an over as he and George Scott put together a partnership of 40.
Fuller's undefeated knock of 46 from 30 balls at least dragged Middlesex's total in the direction of respectability as they posted 131 all out which was aided by six penalty runs awarded for a slow over-rate.
Glamorgan suffered an early casualty in their run chase as Meschede flicked the second ball of the innings into the hands of Gubbins at deep square leg.
Aneurin Donald also perished, swinging at Steven Finn and missing but any whiff of hope for Middlesex was extinguished by Kiran Carlson, who set out to dominate from the off.
He crashed Fuller through the covers for four, following that up with a leg-side six, and had reached 40 from 22 balls when he fell to an impressive catch by Eskinazi, diving forward at deep midwicket.
Colin Ingram took up the baton, smashing an unbeaten 46 off 30 deliveries while Chris Cooke clubbed Stirling for successive sixes to finish on 25 not out and complete a comfortable win.