Chris Lynn’s record-breaking century secured a home quarter-final in the Vitality Blast for the Northamptonshire Steelbacks with two games to spare, after a comfortable win by 53 runs in Cardiff.

The veteran Australian opener lived up to reputation earned with a career tally of more than 9000 T20 runs with 117 from 56 balls, the highest individual score by a Northants batter, on their way to 217 for 7. Calvin Harrison, the other standout performer of the Steelbacks’ campaign ensured the chase was shut out early with 3 for 20 as Glamorgan were bowled out by 164.

Northants bounced back from their only defeat in the competition to get their ninth win and secure top spot in the Central & West group, but Glamorgan’s fate comes down to the final two games with second and third spot in the hands of Worcestershire Rapids and Gloucestershire.

Lynn was supported from the off by Ricardo Vasconcelos for a fast-starting powerplay. Glamorgan attempted an experiment to take out the dangerous Lynn, but Asa Tribe’s second over of the match was hit for three consecutive boundaries over cover.

Ben Kellaway impressed for the home side with the ball. After conceding just three in the opening over, he then went on to take 3 for 22, ending a partnership of 56 between the centurion and Saif Zaib – Lynn earlier put on 58 for the first wicket before Vasconcelos skied McAndrew in the final over of the powerplay.

Lewis McManus had a late flurry to keep the pace of the innings, with Northants certain to pass 200.

Kiran Carlson started by motoring at over a 200 strike-rate, as has been the theme for his season, but sacrificed Will Smale in a mix-up in the process. The captain’s mistimed flick offered a simple return catch for Harrison who impressed in the wickets column and once again with a remarkable economy for a leg-spinner.

The Steelbacks caught especially well: Tribe removed by a diving catch at deep-square, Cooke was held onto off a skier from Harrison and Zaib held onto a one-handed caught-and-bowled in his impressive spell of 2 for 27, playing second fiddle to his spin partner.

James Sales kept his wicket tally ticking to 20, as he bowled the dangerous counter-attacker Dan Douthwaite before Nathan McAndrew fell for a battling 36. The hosts fell well short despite a 40-run partnership for the ninth wicket.