The Cricketer provides all the information you need ahead of a busy day of action as teams start to jostle for position...
When: Sunday, September 12
Where: Blackfinch New Road, Worcester
Lowdown: Worcestershire Rapids sit bottom of the Central Group, but picked up their first win of the tournament on Friday against Somerset thanks to an unbeaten 56 from Ben Cox.
Their opponents, Birmingham, have won their last two white-ball matches, and have shown signs that they are capable of pushing for the knockout-out stages after a mixed start to the Blast.
One to watch: Worcestershire's stars have disappointed, but Pat Brown took three wickets last time out as he looked to finally be returning performances we all know he is capable of.
Tickets: The match will be played behind closed doors.
Weather: Sunny intervals with a gentle breeze in Worcestershire.
Prediction: Birmingham Bears
When: Sunday, September 12
Where: Sophia Gardens, Cardiff.
Lowdown: Last time these two sides met Northants won with four balls to spare, but expect this game to be rather less cagey than that affair.
Northants sit second in the Central Group and have impressed throughout. Their opponents, Glamorgan, have struggled without key men such as Colin Ingram, winning just one match so far - a 15 run win over Gloucestershire.
Glamorgan have to win to realistically stay in contention for the knock-out stages, whilst a victory for Northants go a long way in securing qualification.
One to watch: Paul Stirling is averaging over 40 so far and hit a majestic unbeaten 80 off 48 balls against Worcestershire. The 30-year-old is also bowling some handy off-spin.
Tickets: The match will be played behind closed doors.
Weather: Sunny spells throughout Cardiff.
Prediction: Northants.
Chris Dent will aim to give Gloucestershire another good start
When: Sunday, September 12
Where: The Cooper Associates County Ground, Taunton.
Lowdown: Somerset haven’t picked up a white-ball win since they hit a mammoth 229 against Worcestershire a couple of weeks ago.
Gloucestershire have done better than many expected, sitting top of the Central Group with four wins and only one defeat. Key to their success has been their imposing bowling attack - after just six matches, Tom Smith and Ryan Higgins have already taken 10 wickets each.
One to watch: Chris Dent has hit 200 runs in the tournament so far in just five matches, expect him to continue against a Somerset attack who have one eye on a trip to Lords.
Tickets: The match will be played behind closed doors.
Weather: Sunny spells throughout without highs of 21 in Taunton.
Prediction: Gloucestershire
When: Sunday, September 12
Where: Trent Bridge, Nottingham.
Lowdown: Derbyshire are yet to win a white-ball match this summer and face Notts, who have won four and remain unbeaten thus far.
Arguably, the most impressive side in the tournament thus far, Notts will expect to beat a weak Derbyshire, with a win at Trent Bridge on Sunday almost enough to secure their place in the knockout stages.
One to watch: In his last two innings, Joe Clarke has hit 133 and 77. Impressing in both red and white-ball matches, the Notts No.3 will be expected to cash-in against deflated Derbyshire attack.
Tickets: The match will be played behind closed doors.
Weather: Slight breeze and overcast but some sunny spells.
Prediction: Notts Outlaws
Alex Lees will aim to repeat his Derbyshire knock
When: Sunday, September 12
Where: Emirates Riverside, Chester-le-Street.
Lowdown: Durham have struggled with one win in six and face a Leicestershire side who have had a very mixed run of form in this year's Blast. Last time out, Durham did post 223, but it was against Derbyshire.
One to watch: Alex Lees hit an unbeaten 77 against Derbyshire; runs at the top of the order will be vital if Durham are to avoid defeat against Leicestershire.
Tickets: The match will be played behind closed doors.
Weather: Sunny intervals throughout with highs of 19 at Chester-le-Street.
Prediction: Leicestershire
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