Durham 184 for 5 (Latham 98*, Clark 33) beat Nottinghamshire 150 (Wessels 42, Collingwood 3-25) by 34 runs
Durham skipper Tom Latham led from the front to steer his side to an impressive 34-run win over Notts Outlaws in their Vitality Blast meeting at Trent Bridge.
This was Durham's second shock on an away ground in 48 hours, following their 18-run victory against another highly-fancied side, Birmingham Bears, on Sunday.
Latham scored an unbeaten 98 as his side made 184 for five after being asked to bat first. The left-hander faced 55 deliveries but found himself at the non-striker's end as the innings came to a close.
His contribution proved decisive though, as the defending champions failed to capitalise on an explosive start to their reply and could only muster 150, before being bowled out with 12 balls remaining, with Paul Collingwood taking three for 25 for the visitors.
James Weighell, Durham's seamer, said his side were wary of a repeat of last season when Riki Wessels and Alex Hasles (the latter was away on England duty) took 106 off Durham in the Powerplay.
"It's been a good evening for us," he said. "We were demolished in the Powerplay last year here and we had a feeling it was going to go that way again after four or five overs. This is a very tough place to come to and win."
New Zealand's Latham went past his previous best T20 score of 82 and batted throughout the innings, hitting eight fours and three sixes, one of them a majestic pull from the bowling of international team-mate Ish Sodhi.
Graham Clark shared in an opening stand of 50 with his captain, making a punchy 33, from just 20 balls faced. Collingwood helped propel the total up to 99 for one before the hosts applied the brakes with wickets in three successive overs around the mid-point of the innings.
Ryan Davies applied some timely aggression to help Latham add 59 from only 33 balls. The 21-year old made 16 before falling to an excellent diving catch from wicketkeeper Tom Moores, running towards square leg, giving Harry Gurney figures of two for 23.
Latham started the final over of the innings on 95 but lost the strike as Stuart Poynter muscled a succession of twos.
Steven Mullaney hit the first three balls of the Notts' chase to the ropes, as Will Smith's initial over went for 19 runs. The opening partnership realised 67 runs but then both contributors departed within the space of six deliveries; Wessels was yorked by Chris Rushworth for 42 and Mullaney met the same fate to James Weighell for 25.
Moores, Samit Patel and Billy Root all fell cheaply, leaving Notts on 105 for five after 12 overs, exactly matching the Jets earlier effort.
Dan Christian, the leading run scoring in the competition, threatened to derail the Jets' victory charge with two sixes in his 32 but he received little support at the other end, with Collingwood chipping away with valuable wickets, whilst Imran Tahir also bagged two for 20 against one of his former sides.
The biggest cheer of the evening, in front of a partisan crowd of 10,012 came when Jake Ball, playing after being released from England's ODI squad earlier in the day, hit Nathan Rimmington for a huge six, moments before the same bowler ended the contest with the wicket of Gurney.
In the tight North Group both county sides return to action with home matches on Friday evening; Notts hosting Leicestershire Foxes, with Durham welcoming Worcestershire to Chester-le-Street.