Northants144 for 5 (Vasconcelos 41, Sowter 2-17) beat Durham 140 (Ackermann 70, Sanderson 4-15) by five wickets
Lewis McManus and Ashton Agar held their nerve to take Northamptonshire Steelbacks to victory in the last over of this Vitality T20 Blast thriller at Wantage Road.
Northamptonshire needed 10 runs an over in the last five after falling behind the rate chasing 141 to win, but McManus showed just how much his batting has improved this season, hitting 25 off 16 balls. The hosts went into the last over needing eight to win, but a huge six from Agar, playing his first game for the Steelbacks, took his side to the brink of victory.
Earlier, Ben Sanderson returned career-best T20 bowling figures of 4 for 15, including two in just three balls, as Durham slumped to four for three in the opening three overs. The top three batters all fell without scoring.
Despite wickets falling at regular intervals, Colin Ackermann was the mainstay for the visitors, striking 70 off 52 deliveries with four fours and four sixes to push his side towards respectability as they closed on 140 all out. Left-arm spinner Freddie Heldreich chipped in with three wickets.
Willey set the tone by bowling a testing maiden opening over before Sanderson struck. First, he had Alex Lees caught behind and then got one to jag back to bowl Ollie Robinson.
Things only got worse next over when Graham Clark skied one in the air as he attempted to hit Willey down the ground, Gus Miller taking a good running catch. It left Durham in tatters at 4 for 3 after only 16 deliveries, an Ackermann on drive providing the only runs.
Ben Raine (20), though, quickly got off the mark with a brace of boundaries off Willey. He greeted Ravi Bopara's first over with similar intent, striking consecutive fours before attempting to pull the all-rounder high over deep midwicket, where Ricardo Vasconcelos took a brilliant running catch.
Durham finally passed 50 in the tenth over as Ackermann and Ashton Turner put on 41 for the fifth wicket, Ackerman crisply pulling Miller for four and Saif Zaib square for six.
Turner (19) swung Ashton Agar high over deep midwicket but when he tried to mete out the same treatment to Heldreich, he could only top edge the ball, Vasconcelos running in from the boundary to take a sensational tumbling catch.
Heldreich struck twice in his next over, bowling Bas de Leede and picking up Michael Jones caught by Agar on the long-on boundary.
The tumble of wickets failed to deter Durham who upped the ante. Ben Dwarshuis struck Agar for six and dispatched hit Heldreich for another. Meanwhile Ackermann reached his half-century off 41 balls when he struck Heldreich over deep midwicket.
Sanderson made a crucial double breakthrough when he returned to bowl the penultimate over, having Dwarshuis caught behind off a top-edge and bowling Callum Parkinson.
Ackermann finally departed, caught off Raphy Weatherall in the 20th over, but not before he struck another six down the ground.
Durham bowled tightly up top, Northamptonshire finding it difficult to time the ball. The first boundaries did not come until the fourth over when Vasconcelos (41) scooped de Leede for six and four. Easing into his work, he then garnered two legside boundaries off Dwarshuis.
The hosts lost their first wicket when Raine had Matthew Breetzke caught off an attempted pull, but Vasconcelos continued to make hay, taking consecutive fours off the same bowler.
Willey, too, was proactive, smashing Ackermann for two boundaries, but he fell soon afterwards when he tamely chipped a return catch back to Nathan Sowter. The Steelbacks lost a second when Parkinson trapped Vasconcelos lbw. The opener had passed 1,000 runs in T20 cricket for Northamptonshire, with Zaib passing the same milestone shortly afterwards.
Northamptonshire lost a fourth when Bopara picked out Turner at long-off off Sowter to leave them 86 for four at the end of the 14th over, still needing 55 to win.
With Durham keeping up the pressure in the field, McManus eased home nerves slightly with a six off Sowter and slapping Parkinson down the ground. He and Zaib shared an enterprising stand of 32 in 3.3 overs which ended when Zaib chipped Raine straight to mid-off.
McManus swung a huge legside six off the penultimate over from Dwarshuis to keep Northamptonshire in the hunt, leaving them needing eight off the last over.
Parkinson bowled a dot ball first up, but Agar flicked him high behind square for six before a wide brought the scores level. After another dot ball, Agar ran a single to earn victory.
