The Vitality Blast returns on Wednesday, with the format reverting to two groups of nine rather than last summer's three groups of six. Fixtures are packed in to keep the competition into a relatively tight group-stage window, with the quarter-finals from August 24-27 and Finals Day on September 18. In a change to previous regulations, counties can register three overseas players simultaneously - though can still only field two in a playing XI.
So who are the runners and riders in the North Group?

Birmingham Bears

Last season: 3rd in Central Group
Coach: Mark Robinson
Captain: Will Rhodes
Overseas players: Carlos Brathwaite, Pieter Malan
Championship contrast: Ed Pollock, Adam Hose and Carlos Brathwaite add power to the batting line-up while Jake Lintott, the left-arm wristspinner, returns after a breakthrough season in 2020, when he took 10 wickets and went at only 6.30 an over. Henry Brookes should be fit at some stage but recently suffered a thigh injury.
Key man: Carlos Brathwaite arrives on the back of Big Bash success for the Sydney Sixers over the winter, where he took 16 wickets and went at 8.02 an over despite often bowling at the death and in the Power Surge. He has struggled badly for runs in T20 of late with teams targeting him with spin, but warmed up for the Blast with 116 off 54 for Warwickshire's 2nd XI last week. He is based in Oxford, meaning a short commute up to Birmingham.
One to watch: Only Andre Russell has scored more T20 runs than Ed Pollock at a higher career strike rate (169.45 to 167.59) but he is clinging onto his contract at the club after two lean seasons and has struggled against spin early on. He has found form for the 2nd XI of late but the Bears need to accept that his high-risk methods means he will fail regularly and give him a long rope.
Verdict: Lintott and Danny Briggs are an excellent spin combination but they are light on proven T20 batters. Matt Roller
Bet365: 12/1

Derbyshire Falcons

Last season: 6th in North Group
Coach: Dominic Cork
Captain: Billy Godleman
Overseas players: Logan van Beek, Dustin Melton
Championship contrast: Derbyshire's head of cricket Dave Houghton has admitted that the county has been playing the worst Championship cricket in the country, so a fresh start is welcome. But they won fewer Blast matches than anyone in 2020 so there is a danger of more of the same. Netherlands seamer Logan van Beek, who had moderate success in 2019, steps in after an ill-starred signing of Billy Stanlake and Alex Thomson has been loaned from Warwickshire as a spin option.
Key man: Until the eve of the tournament it was Australian wicketkeeper-batter Ben McDermott, son of Craig, the former international fast bowler. Now he is heading to the West Indies with Australia and Derbyshire simply do not have the resources to cover his absence. An alternative key man is urgently needed. We can't keep writing "Wayne Madsen" every year.
One to watch: Alex Thomson put a career teaching PE on hold to try to make it in county cricket and it could be now or never. An early-season loan to Durham brought no benefits when he never got beyond the 2nd XI so Houghton's talk of him being a good squad option might concern him. If Thomson doesn't make the side then legspinner Mattie McKiernan probably will.
Verdict: Can't be any worse then their four-day stuff - but that's not saying a great deal. David Hopps
Bet365: 25/1

Durham

Last season: 4th in North Group
Coach: James Franklin
Captain: TBC
Overseas players: Cameron Bancroft, David Bedingham
Championship contrast: A delay in announcing Durham's T20 captain indicates that it is not beyond possibility that Scott Borthwick, who has supervised a successful Championship campaign, will refresh himself mentally and hand over the captaincy. Durham, though, can make use of his batting in a squad not overstocked with options; Liam Trevaskis can be expected to bowl left-arm spin and there should be a spot for Graham Clark, who struck at 171.71 last season, at the top of the order.
Key man: Ben Stokes' finger injury, suffered in his only IPL appearance for Rajasthan Royals, is responding rapidly to treatment and confidence is growing that he might be able to make a substantial contribution to the first half of the Blast campaign after a three-year absence. The value of England players in at least some of the Blast cannot be overstated and future fixture lists should be drawn up with that in mind.
One to watch: Matty Potts has broken into Durham's four-day side this summer, proof of further development after he broke his career-best figures in the Blast three times in 2020. His threat in the powerplay overs was enough to make him Durham's T20 player of the year and to win him a contract in the Hundred with the Northern Superchargers.
Verdict: Durham will cope better than most with the relaid Riverside square and that can help them reach the quarter-finals. DH
Bet365: 25/1

Lancashire

Last season: 2nd in North Group, semi-finals
Coach: Glen Chapple
Captain: Dane Vilas
Overseas players: Dane Vilas, Finn Allen
Championship contrast: Instead of the likes of Keaton Jennings and Luke Wells in the top three, Alex Davies (Lancashire's top T20 run-getter for the past three seasons) will be accompanied by two of Jos Buttler, Liam Livingstone and Finn Allen. Spin has played a large part in Lancashire's T20 tactics - Matt Parkinson is now getting four-day opportunities, but in T20 he could be joined by Tom Hartley, and batting allrounders Steven Croft and Livingstone.
Key man: Matt Parkinson has bowled two of the Championship's most stunning deliveries of the season - rehashing Shane Warne's Ball of the Century™ to bowl Northants' Adam Rossington at Old Trafford and then showing he could do it to left-handers too, befuddling Sussex's Delray Rawlins. He has been an indispensable part of Lancashire's T20 challenge in recent seasons and any England call-up - although he would have to displace Adil Rashid for that - would shake them.
One to watch: Breakthrough Kiwi batsman Finn Allen is a hot tip as one of the new stars of this season's tournament. Allen had a stunning debut season for title-winning Wellington Firebirds in New Zealand's Super Smash, amassing 512 runs at an average of 56.88 and strike rate of 193.93. That was enough to win a call up as a replacement player for Royal Challengers Bangalore without managing to get onto the field.
Verdict: Lancashire are currently topping their group in the Championship and they can emulate that success in the North Group. DH
Bet365: 8/1

Leicestershire

Last season: 3rd in North Group, quarter-finals
Coach: Paul Nixon
Captain: Colin Ackermann
Overseas players: Naveen-ul-Haq, Josh Inglis
Championship contrast: Scott Steel, who formed a dangerous T20 opening partnership for Durham in 2019 with D'Arcy Short, opted to move to Leicestershire last winter and will be bursting for an opportunity after good returns in 2nd XI cricket. Arron Lilley, a former T20 winner with Lancashire, is another white-ball specialist and potential game-changer. Two intriguing overseas signings in Naveen-ul-Haq and Josh Inglis can also be expected to be value-for-money additions with bat and ball.
Key man: Josh Inglis experiences professional cricket in England for the first time, at 26, and is billed by his coach, Paul Nixon, as "young, hungry and keen," and in keeping with the sort of T20 squad he is seeking to develop. Inglis had an excellent 20-21 Big Bash, shifting down from the top of the order to No. 4, to help Perth Scorchers to the final, and his Leeds birthplace (he played age group cricket for Yorkshire) makes his future even more intriguing.
One to watch: Left-arm spinner Callum Parkinson is overshadowed by his spin-bowling twin brother, Matt, but he has taken the most wickets for Leicestershire in the Blast in each of the last three seasons and his status has grown enough for Worcestershire to have tried to entice him away from Grace Road over the close season.
Verdict: Leicestershire missed out on Finals Day in 2021 after a tied quarter-final against Notts Outlaws was decided on powerplay runs and are quite capable of springing a surprise or two. DH
Bet365: 25/1

Northamptonshire

Last season: 2nd in Central Group, quarter-finalists
Coach: David Ripley
Captain: Josh Cobb
Overseas players: Mohammad Nabi, Wayne Parnell
Championship contrast: Unashamedly focused on T20 from 2013 onwards but balance has shifted back towards Championship of late. Josh Cobb, Mohammad Nabi, Brandon Glover, Richard Levi and Graeme White dovetail with the four-day regulars.
Key man: Josh Cobb had a poor season with the bat in 2020, failing to make a half-century, but his offbreaks in the powerplay remain hugely underrated (he went at 5.86 an over in the first six last year) and he won a deal with Welsh Fire in the Hundred's re-draft early this year. Now a white-ball specialist, he is an astute captain but will need to fire more regularly from No. 3.
One to watch: Brandon Glover was the second-highest wicket-taker playing for Netherlands in the T20 World Cup Qualifier in late 2019, bowling hard lengths into the pitch in the enforcer role. That Dutch heritage means he is eligible as a local player, and joined Northants last summer on Chris Liddle's recommendation. Seven wickets and an economy rate of 9.11 was a middling first season in the Blast.
Verdict: Batting line-up looks light in Paul Stirling's absence, and inexperienced T20 batters like Ricardo Vasconcelos and Saif Zaib will need to step up if they are to challenge. MR
Bet365: 20/1

Nottinghamshire

Last season: 1st in North Group, Winners
Coach: Peter Moores
Captain: Steven Mullaney
Overseas players: Dane Paterson
Championship contrast: Notts have lost two white-ball specialists because Australia have come calling for their skipper Dan Christian, at 38, and Harry Gurney has retired because of a shoulder injury that also excluded him from their successful Blast campaign in 2020. But they have an influx of highly-seasoned T20 campaigners in Samit Patel, Alex Hales, Jake Ball and Peter Trego. Their fielding could come under stress, although ironically it was neighbours Leicestershire, with their accent on youth, whose fielding lapsed during last year's quarter-final.
Key man: Notts' pedigree is unquestionable: semi-finalists three times in the last four seasons, winners twice, including last year, and among the favourites again. But they lack left-arm spinner Imad Wasim because of the clash with the rearranged Pakistan Super League, and Jake Ball has not played any cricket since April 9 because of a back injury. That leaves a huge onus for wickets with South African Dane Paterson, an experienced bowler who is renowned for his economical death bowling but has not played in the format for 18 months.
One to watch: Hardly an unknown quantity admittedly, but what should we expect from Alex Hales? It appears that England have taken a view that he is not to be trusted, which, at 32, leaves his final batting years to be played out on T20 circuits throughout the world as long as he can avoid further trouble. A fine natural batting talent with destructive tendencies in more ways than one.
Verdict: An ageing Notts side lacking the inspirational Christian and with dubious bowling and fielding resources are not persuasive short-priced favourites: avoid. DH
Bet365: 6/1

Worcestershire

Last season: 6th in Central Group
Coach: Alex Gidman
Captain: Moeen Ali
Overseas players: Ish Sodhi, Ben Dwarshuis
Championship contrast: Overseas signings Ish Sodhi and Ben Dwarshuis add quality and variety to the bowling attack, while Ross Whiteley and Riki Wessels are better-suited to this format than the four-day game. Pat Brown is also due to return but Jack Haynes is injured. New Road pitches have been incredibly slow in the Championship - will they be any quicker in the Blast?
Key man: Moeen is the talisman but likely to be on England duty for at least half of the group stage and Ben Dwarshuis could be the missing link. Worcestershire struggled to cope with Wayne Parnell's absence last summer after he had played a crucial role in their runs to the previous two finals, and in Dwarshuis - a key component of the Sydney Sixers side that has won the last two Big Bashes - they have a similarly effective left-arm seamer who can take powerplay wickets and keep things tight at the death.
One to watch: Pat Brown has fallen away somewhat since finishing as the leading wicket-taker when Worcestershire won the competition in 2018, with regular back injuries halting his progress. He went at 10.85 an over last summer and is out of the England reckoning so has plenty to prove - though his fitness is the first thing, and he is due to miss the opening rounds with more back trouble.
Verdict: 2018 winners and 2019 runners-up had a horror season last summer but should compete for a quarter-final spot thanks to their stock of allrounders. MR
Bet365: 14/1

Yorkshire

Last season: 5th in North Group
Coach: Andrew Gale
Captain:David Willey
Overseas players: Lockie Ferguson, Duanne Olivier, Mat Pillans
Championship contrast: Yorkshire welcome back England's Adil Rashid and Jonny Bairstow for the first half of the tournament. One of them had the candour to operate openly under a white-ball only contract and has been criticised for it; the other is just rarely available and largely escapes grumbles. Bairstow gets to open the innings and keep, which is what he would have wanted. The players signed as T20 specialists, Josh Poysden and Mat Pillans, have largely failed to impress, but Lockie Ferguson brings international quality.
Key man: England took a look at Adam Lyth as a Test opener and it didn't work out (he is far from alone in that), but he remains one of the most dangerous T20 openers around and is unfortunate to be playing when England's resources are so deep. He consistently scores at a strike rate in excess of 150 and there is no better opener at peppering boundaries through backward point. His inoffensive offspin also picks up useful wickets and he concedes his Championship spot at slip to excel in the deep in T20.
One to watch: David Willey did not quite make it to England's World Cup final in 2019, but he can embolden Yorkshire's T20 approach in his second season as captain - apparently, he has even helped to design their shirt. He is blessed with some excellent young strokemakers such as Harry Brook and Tom Kohler-Cadmore (moved down to No. 4 because of Bairstow's availability). Willey's influence on a number of talented young allrounders - think Jordan Thompson, Matt Fisher, and the somewhat forgotten Matthew Waite - could be crucial.
Verdict: Yorkshire are T20's great underachievers with two Finals Day appearances in the past 10 years and under Willey's captaincy they can change all that. DH
Bet365: 10/1