Gloucestershire fell to a second defeat inside 24 hours as Glamorgan took the Severn-side derby spoils.
Glamorgan kept their knock-out qualification hopes alive with a 32-run win over their local rivals.
After being put into bat, Glamorgan reached a respectable 183-5 from their 20 overs despite their injury-affected batting line-up.
Northeast led the way with 60 not out from 48 balls, following on his impressive T20 form so far this season.
With a recent calf injury to Colin Ingram to go with the already injured David Lloyd and Eddie Byrom, Glamorgan were forced to change-up their batting plans.
After Prem Sisodiya’s new-found role as an opening batter didn’t pay dividends, Northeast batting at number four played his usual, anchoring role on what was a difficult pitch to push on from a start as represented throughout the scorecard.
Timm van der Gugten also played an important role with a 19-ball 38 at number six including four sixes in his partnership of 58 with Northeast at the back end of the innings.
After a steady powerplay and consistent run-scoring in the middle, starts from Billy Root and Chris Cooke allowed Glamorgan to accelerate to a run rate just shy of 12 in the final six overs.
Gloucestershire looked to always be behind the rate on the tricky pitch despite a partnership of 45 between Ben Charlesworth and Grant Roelofsen keeping wickets in hand for the middle and lower order.
Charlesworth’s 45 from 28-balls stood out in the visitors’ innings as the only batter to show fluency in his stroke making. However, with a large amount of responsibility on his shoulders, the run-rate eventually became too much of an ask for the young man.
Glamorgan bowlers enjoyed the more favourable pitch compared to previous matches as Hatzoglou picked up 3-23 supported by 2-25 and 2-29 from van der Gugten and Ruaidhri Smith, respectively, to kill the game off.
Despite a flourishing finish from David Payne getting Gloucestershire to 151-8, the five wickets for 15 runs that fell prior to his cameo did the damage that was required to give Glamorgan the points.