|T20 Blast, SSE Swalec Stadium, Cardiff|
|Somerset 159 for 5 (20.0 overs)|
|Glamorgan 43 for 1 (6.0 overs)|
|Glamorgan won by 2 runs (D/L)|
Glamorgan edged a narrow win over Somerset by two runs on the Duckworth-Lewis system as persistent rain halted their innings.
Somerset recovered from a shaky start to set a target of eight runs an over, with Tom Cooper blasting six sixes in a career-best 84 not out.
The home side nudged ahead of their required target in the sixth over, aware play could be interrupted.
It was their second win inside 24 hours after victory at Gloucestershire.
Toby Radford's side are level on points with group leaders Hampshire, but behind on overall net run-rate.
Glamorgan unsurprisingly put Somerset in to bat in murky conditions with Wayne Parnell's menacing spell removing Marcus Trescothick and former Glamorgan man Jim Allenby either side of an early rain-break.
Craig Meschede chipped in with the wicket of Peter Trego to leave Somerset struggling at 26 for 3.
James Hildreth and South Australia's Cooper eventually got some momentum into the innings with a stand of 47 before Hildreth was bowled for 28 trying to force Dean Cosker away.
Cosker also got rid of Johan Myburgh but Cooper took control of the final stages, smashing sixes all around the ground as Somerset took 48 runs off the 18th and 19th overs.
He and Lewis Gregory added a spectacular 74 in just 4.4 overs, helped by several spilled catches in the deep, to leave Glamorgan facing a challenging chase.
Meschede struck a quickfire 18 to launch the home reply before falling to a brilliant Gregory boundary catch.
Then a pair of boundaries from Colin Ingram and one from Jacques Rudolph as the rain grew heavier allowed Glamorgan to edge past the Duckworth-Lewis par score, moments before the umpires took the teams off.
Rudolph and Somerset captain Alfonso Thomas appeared to be exchanging terse words as the players reached the dugouts.
But there was no chance of Somerset having a chance to strike back, and play was called off at just after 6pm as Cooper's valiant efforts proved in vain.
Somerset faced a rapid turnaround for a home Championship date with Nottinghamshire, while Glamorgan have a Monday start away to Surrey.