Bethell held his composure in the final over to smash a six and a four in back-to-back balls to steer Birmingham over the line with three balls to spare, edging them closer to a quarter-final berth
Chester-le-Street: Durham 146-5, Birmingham Bears 149-8 - Birmingham Bears win by two wickets
Jacob Bethell held his nerve under pressure in the final over to guide Birmingham Bears to a two-wicket victory over Durham in a thriller at Seat Unique Riverside, keeping the visitors on top of the Vitality Blast North Group.
The Bears were miserly with the ball after winning the toss. Hassan Ali was excellent at the top of the order and collected figures of 2 for 15 from his four overs, while Danny Briggs also claimed two strikes. Ollie Robinson and Ashton Turner notched fifties, but Durham's total of 146 for 5 looked short of par at the interval.
Alex Davies and Rob Yates led an explosive start to the Bears' chase, sharing an opening stand of 80 to put the visitors ahead of the rate.
But Nathan Sowter continued his impressive campaign with two wickets to halt the Birmingham charge. Ben Raine then set nerves jangling with two in two in the 17th over and he performed heroics again with the same feat in the 19th.
The game turned again when Bethell held his composure from the final over to smash a six and a four in back-to-back balls to steer Birmingham over the line with three balls to spare, edging them closer to a quarter-final berth.
After Graham Clark scored three early boundaries, Durham's momentum was halted losing both openers within three balls. Chris Woakes made the breakthrough on his return as Alex Lees was undone by a slower delivery before Clark was bowled by Hassan Ali.
Rob Yates got Birmingham off to a flier (David Rogers/Getty Images)
Ali produced a brilliant spell with the new ball, bowling three overs for the cost of just seven runs, limiting the hosts to 29 from the powerplay.
The Bears continued to restrict the Durham batting ranks as the run rate hovered at just below six an over. The pressure to score allowed Briggs to strike in successive deliveries. Michael Jones was caught on the fence by Jake Lintott, who produced a clever catch on the rope to prevent a maximum, while Brydon Carse fell first ball.
At 60 for 4, the hosts could ill-afford to lose further wickets. Robinson and Turner duly responded with an excellent partnership worth 86 to allow Durham to post a competitive total. Turner found his timing against the Birmingham spinners and raced to his half century from only 29 balls with seven fours and slog-sweep six against Lintott.
Robinson was more sedate compared to his teammate, but still brought up his fourth fifty of the season with a massive strike over the rope against Woakes. He tried to add another off the final ball from Ali, only to be caught on the relay by Lintott and Ed Barnard, ending the Durham innings on 146 for 5 from 20 overs.
Birmingham had no difficulty adjusting to the pitch in the powerplay and made the chase seem straightforward.
Davies and Yates found the boundary with ease without taking risks, racing to fifty after 4.2 overs. The Bears were a staggering 37 runs ahead of the home side at the end of the powerplay, ending the opening six overs 66 without loss.
Nathan Sowter is having a terrific campaign (Stu Forster/Getty Images)
Davies and Yates both fell for 40 as Liam Trevaskis and Wayne Parnell prevented the visitors from racing away with the chase.
On his 400th T20 appearance, Glenn Maxwell's attempt to reverse sweep Sowter to the rope ended his knock for 14 and the leg-spinner sent Dan Mousley on his way to put the pressure on.
Raine set up a tense finale by matching Briggs' exploits removing Chris Benjamin and Ed Barnard in successive deliveries.
The right-armer then performed similar heroics to dismiss Woakes and Ali with two in two in the 19th. But Bethell dispatched Trevaskis for a six and four to guide his team to victory in the final over.
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