12 teams; 8 places - T20 Blast goes down to the wire

Birmingham
Current Position: 1st; Highest Possible Position: 1st; Lowest Possible Position: 2nd; Opponents: Yorkshire (8th)

Birmingham's one-run victory against Northamptonshire on Wednesday confirmed a top-two finish for them, ensuring a home quarter-final. However, because Worcestershire's Net Run Rate is superior to Birmingham's, Birmingham can slip to second place if they lose to Yorkshire and Worcestershire beat Lancashire. A No Result will guarantee Birmingham a first placed finish. Birmingham have won their last five T20 matches against Yorkshire, who have, for the second consecutive week, named a youthful squad. This will be Brendon McCullum's final match for Birmingham before international duty takes him away.

Worcestershire
Current Position: 2nd; Highest Possible Position: 1st; Lowest Possible Position: 2nd; Opponents: Lancashire (5th)

Worcestershire were guaranteed a top-two finish and a home quarter-final when Northamptonshire fell narrowly short against Birmingham on Wednesday. Worcestershire can still finish first if Birmingham are beaten by Yorkshire and Worcestershire beat Lancashire which will move them level on points with Birmingham, which by default will take them first with their Net Run Rate already superior to that of Birmingham's. A No Result will prevent Worcestershire finishing first regardless of what happens to Birmingham.

Worcestershire have been forced to make a change to last week's squad, with overseas player Colin Munro having left to join New Zealand's preparation for their tour of South Africa. He is replaced by Joe Clarke. This is the only match in the North Group between two teams who can both feature in the quarter-finals.

Northamptonshire
Current Position: 3rd; Highest Possible Position: 3rd; Lowest Possible Position: 5th; Opponents: Durham (6th)

If Northamptonshire win they will finish third. If they lose and both Lancashire and Nottinghamshire win they will finish fifth. If Northamptonshire win and only one of either Lancashire and Nottinghamshire win they win finish fourth. If both Lancashire and Nottinghamshire win, a No Result for Northamptonshire will mean Net Run Rate will split the three teams.

Lancashire
Current Position: 4th; Highest Possible Position: 3rd; Lowest Possible Position: 5th; Opponents: Worcestershire (2nd)

Even if Lancashire beat Worcestershire they will not be guaranteed a top four finish because if Northamptonshire win and Nottinghamshire also win by a big enough margin to move their Net Run Rate above Lancashire's, Lancashire will slide to fifth. However, if Lancashire win and one or both of Northamptonshire and Nottinghamshire lose Lancashire will be guaranteed a top four finish. Likewise if they all three of Northamptonshire, Lancashire and Nottinghamshire win, Lancashire will finish in the top four if they can keep their Net Run Rate ahead of Nottinghamshire's.

A No Result for Lancashire will guarantee them a top four finish if Nottinghamshire lose but if Nottinghamshire win Lancashire will need Northamptonshire to lose for Lancashire to finish in fourth which will be done virtue of them already having a superior Net Run Rate.

Lancashire have named a 14-man squad for the match against Worcestershire, who are experiencing their most successful ever T20 season having already won more matches (9) this season than they've ever managed in one campaign before.

Nottinghamshire
Current Position: 5th; Highest Possible Position: 3rd; Lowest Possible Position: 5th; Opponents: Leicestershire (7th)

If Nottinghamshire win for what will be the fourth time in a row and one or both of Lancashire and Northamptonshire lose Nottinghamshire will finish in the top four. If Nottinghamshire, Lancashire and Northamptonshire win then Nottinghamshire will have to elevate their Net Run Rate above Lancashire's to finish fourth. If Nottinghamshire's match is a No Result then they can qualify if Lancashire lose or if Northamptonshire lose and their Net Run Rate drops below Nottinghamshire's in the process.

Nottinghamshire have named a full-strength squad and will face a Leicestershire team missing Grant Elliot, the O'Brien brothers and Rob Taylor who are all on international duty.

Durham (6th), playing Northamptonshire, Leicestershire (7th), playing Nottinghamshire, and Yorkshire (8th), playing Birmingham, are fighting for places six to eight, while Derbyshire (9th), who played their fourteenth and final match last week are already consigned to a last place finish.

Kent
Current Position: 1st; Highest Possible Position: 1st; Lowest Possible Position: 1st; Opponents: Essex (3rd)

Kent will finish first and are guaranteed a home quarter-final regardless of the result against Essex. However, their qualification has not stopped them naming a full-strength squad for the match.

Hampshire
Current Position: 2nd; Highest Possible Position: 2nd; Lowest Possible Position: 5th; Opponents: none.

Hampshire's hard-fought win against Somerset on Thursday has kept their chances of reaching the quarter-finals for the seventh consecutive season alive. Hampshire will qualify if just one of Sussex, Essex or Glamorgan fail to win. If all three of them win then two of Hampshire, Essex and Glamorgan will qualify on Net Run Rate.

Sussex
Current Position: 3rd; Highest Possible Position: 2nd; Lowest Possible Position: 4th; Opponents: Surrey (7th)

Sussex will guarantee themselves a top-four finish and a home quarter final if they win their final match against Surrey. If either one of Essex or Glamorgan lose they will also be guaranteed qualification. If both Essex and Glamorgan win then Sussex will either have to win to qualify or get a No Result and sneak through on Net Run Rate.

Essex
Current Position: 4th; Highest Possible Position: 2nd; Lowest Possible Position: 7th; Opponents: Kent (1st)

If Essex win they are through by virtue of possessing a higher Net Run Rate than Hampshire, if they lose they will be surpassed by Glamorgan or Gloucestershire on points or Net Run Rate respectively, depending on who wins that encounter, and slide out of the top four. A No Result will be enough for them if Glamorgan lose or if Sussex lose and their Net Run Rate drops below Essex's.

Glamorgan
Current Position: 5th; Highest Possible Position: 2nd; Lowest Possible Position: 7th; Opponents: Gloucestershire (6th)

If either Essex or Sussex lose a win for Glamorgan will guarantee them a top four finish after the Welsh county beat South Group leaders Kent last week. However, if all three of them win then Sussex will qualify and Net Run Rate will separate Glamorgan, Essex and Hampshire to determine the top four. If Glamorgan lose they will be out by virtue of already possessing a lower Net Run Rate than Gloucestershire who would be level on points with them. A No Result would take Glamorgan through if Essex lost.

Glamorgan, who have selected fewer squad players than any county this season, have named an unchanged 12-man squad for the only match in the country on the final day of the league-stage that features two teams not yet qualified but still able to qualify.

Gloucestershire
Current Position: 6th; Highest Possible Position: 4th; Lowest Possible Position: 7th; Opponents: Glamorgan (5th)

Gloucestershire can only qualify if they win against Glamorgan and Essex lose and will do so by virtue of already possessing a superior Net Run Rate to Essex which will only be furthered by a win for them and a loss for Essex. A No Result will eliminate Gloucestershire.

Gloucestershire captain Michael Klinger is the season's top run-scorer and needs just 25 more runs to surpass the highest tally ever in a season of 653, set by Jason Roy last season.

Surrey Current Position: 7th; Highest Possible Position: 4th; Lowest Possible Position: 7th; Opponents: Sussex (3rd)

Surrey's defeat to bottom place Middlesex on Thursday takes their fate out of their own hands and would make qualification a small miracle. They are similarly placed to Gloucestershire, only with a worse Net Run Rate and higher placed opponents on the final day.

So how can they possible remedy that? Surrey can qualify if they win against Sussex and Essex lose against Kent, and in the process of those results Surrey maintain a higher Net Run Rate than Essex; or similarly if they win against Sussex and Gloucestershire win against Glamorgan but Surrey obtain a higher Net Run Rate than Gloucestershire in the process. A No Result will eliminate Surrey who have named an unchanged 12-man squad from Thursday's defeat against Middlesex.

Somerset (8th) play Middlesex (9th) with neither county capable of making the top four. Both teams have selected young squads, with an eye towards the future. Somerset's T20 captain Alfonso Thomas has been dropped following a poor season.