Struggling Surrey need to curb Gayle's run spree

Somerset v Surrey, Taunton, 5.30pm
Firm friends Chris Gayle and Kevin Pietersen have spent the week mucking around together in the latter's London bar and promoting the CPL, which they both fly out to this weekend. They will not, however, be reunited at Taunton on Friday as Gayle makes his final appearance - two games earlier than anticipated - in front of his adoring Somerset faithful. Passers by beware; the area around the County Ground will be peppered one last time. Pietersen will play against Sussex at Arundel on Sunday - where 5,000 advance tickets have already been sold and a crowd of upwards of 7,500 is expected - but not in this fixture. He plays at Arundel in place of Kumar Sangakkara, who is in the squad for this match.

Going into his fourth match, Gayle has already scored 328 runs, as well as endearing himself to all-comers with signing sessions and plenty of fan interaction. After missing their Championship fixture this week, Jamie Overton returns to the Somerset squad. For bottom of the table Surrey, who haven't won since the opening weekend, regular openers Jason Roy (England duty) and Steven Davies (hand injury) are missing, while 17-year-old allrounder Sam Curran - younger brother of bowler Tom - is in the squad for the first time.

Gloucestershire v Glamorgan, County Ground, Bristol, 5.30 pm
Gloucestershire return home after losing to Essex on Thursday at the start of a crucial weekend in which they play three times, with a fixture against Middlesex in Richmond on Sunday following their this match. Skipper Michael Klinger continued his marvellous form at Chelmsford, with a second century in three matches to go with 69* against Kent last Friday and some excellent Championship form, too. Hamish Marshall is in contention to return after a calf injury ruled him out against Essex. Glamorgan - who have won two and lost two - hope that South African left-armer Wayne Parnell will be able to endure the rigours of games on consecutive days as he struggles with a groin problem ahead of their fixture against Somerset on Saturday.

Kent v Hampshire, Canterbury, 6.30pm
After last week's defeat to Gloucestershire at Beckenham, Kent's position atop the South Group is precarious. Their two defeats - at Beckenham and a drubbing at Lord's - have been hefty, leaving them with the worst NRR in the Group. They are without Sam Billings, who is with England and is replaced by Ryan Davies, who will make his T20 debut for the club, while James Tredwell returns to the squad after injury. Skipper Sam Northeast, who already has 344 runs in the competition, and dashing finisher Alex Blake will have fond memories of the reverse fixture at the Ageas Bowl, where they shared 108 to win from a seemingly hopeless position. Hampshire were the victims of a Chris Gayle special last week and this will be the final outing of their own West Indian, Fidel Edwards, before he jets off to the Caribbean Premier League on Sunday.

Sussex v Essex, Hove, 7pm Are Essex on the charge? Four defeats in their first five have been followed by consecutive victories over Surrey and Gloucestershire and, although they have played more games than any other team, they have crept into the top half of the South Group. For Sussex, Craig Cachopa will continue to keep wicket, Tymal Mills is in the squad to face his former county, but his fast bowling colleague Ajmal Shahzad has not recovered from a bicep injury in time, despite playing for the Second XI earlier in the week. Jimmy Anyon and Lewis Hatchett are still injured, while the seam bowling stocks are further depleted by Chris Jordan's England call.

Leicestershire v Northamptonshire, Grace Road, 5.30pm Last Friday night's destruction of Nottinghamshire, with Umar Akmal smashing 76 off 49 balls in front of a crowd of 11,000, was further evidence that there is at least a little feelgood factor back at Grace Road. This week, Akmal goes head-to-head with his longtime Pakistan colleague Shahid Afridi as Northamptonshire - fresh from their home win over Derbyshire - visit. Leicestershire welcome back the O'Brien brothers, who missed last week's victory when on Ireland duty. After three consecutive defeats, Northants got their season on the move with Thursday's win over Derbyshire, but remain bottom of the North Group. David Willey, who put in an inspired all-round performance in Thursday's win, is not available as he returns to join up with England's ODI squad at the Oval.

Lancashire v Derbyshire, Old Trafford, 6.30pm Jos Buttler won the Roses Clash at Headingley for Lancashire last Friday with some staggering striking but after more heroics this week - this time for England against New Zealand - he is absent on further international duty. His place is taken by regular understudy Alex Davies. Derbyshire are up against it; they've lost all of their last 11 T20s away from home, including Thursday's defeat to Northamptonshire, as well as seven of their last eight T20 matches against Lancashire, who in turn have won 12 of their last 14 home T20s.

Birmingham Bears v Nottinghamshire, Edgbaston, 6.30pm Champions Birmingham Bears are lurking with intent in fourth place in the North Group; they haven't lost since Alex Hales's six-sixes show in the reverse fixture on the tournament's opening night. Nottinghamshire sit second in the group and will be without Hales and regular skipper James Taylor (both are on international duty) for the clash, with Riki Wessels taking over for the first time, while Harry Gurney is an injury doubt and Darren Sammy will make his final appearance before heading off to play for St Lucia Zouks in the CPL. Birmingham have named an unchanged squad after Ian Bell's 90 led them to a superb win over Durham last week.

Durham v Worcestershire, Chester-le-Street, 7pm Worcestershire have added to leg-spinner Brett D'Oliveira to the squad that came up short against Nottinghamshire on Sunday and both Moeen Ali and Saeed Ajmal will play. Durham have already played seven games - three more than their opponents - and, having won four of them, sit top of the North Group. They are also top of the County Championship but go into this game without England's Ben Stokes. Their captain Paul Collingwood admits he looks at their patchy batting form and wonders just how they have scrapped their way into this position.