County Championship team news
Chris Nash is likely to bat at number three with Richard Montgomerie and Carl Hopkinson resuming their opening partnership.
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Formidable partnership: Marcus Trescothick (above) will hope to follow up last week's monster total against Devon as he and former Australia batsman Justin Langer open for Somerset against Middlesex
Fast bowler Jason Lewry, who has missed most of pre-season with a virus, has been named in the 13-man squad.
Pakistan seamer Rana Naved-ul-Hasan arrived late due to flight problems but is also set to play in a side captained by Chris Adams.
Pakistan international seamer Yasir Arafat is set to make his Kent debut against former team.
All-rounder Ryan McLaren, a Kolpak signing, also debuts but seamer Amjad Khan is out for the season after knee surgery and Andrew Hall is still on World Cup duty with South Africa.
Exiled England wicketkeeper Geraint Jones will be looking to impress as he attempts to fight his way back into international recognition while Robert Key continues to captain the side.
Leicestershire hope to field India left-arm seamer RP Singh for their opening LV County Championship match against Nottinghamshire at Trent Bridge, despite him arriving in the country less than 24 hours before the game.
Singh, who has played two Test matches and 20 one-day internationals, will team up with Leicestershire's other overseas player, Mansoor Amjad, the 19-year-old leg-spinning all-rounder from Pakistan.
Opening batsman Darren Robinson will lead the side in place of club captain Jeremy Snape, while wicketkeeper Tom New steps in for Paul Nixon, who is still on England duty - as is seamer Stuart Broad.
England A batsman Will Jefferson is expected to be fit to make his debut for Nottinghamshire.
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Jefferson missed the MCC v Sussex match but is expected to recover in time with David Hussey leading the side as Stephen Fleming is still with New Zealand at the World Cup.
AJ Harris has a foot injury and is not expected to recover in time but Notts do include new signings Bilal Shafayat and Mark Wagh.
Ian Salisbury and Jade Dernbach will miss Surrey's LV County Championship opener against Yorkshire at the Brit Oval with muscle injuries.
Leg-spinner Salisbury has strained an arm and medium pacer Dernbach a thigh but James Ormond features in a 12-man squad after an injury-ravaged 2006.
Recent Australian signing Steve Magoffin is included with former England leg-spinner Chris Schofield and batsman Mark Ramprakash, who scored over 2,000 championship runs in 2006.
Worcestershire will be without Australian seamer Matt Mason for their LV County Championship Division One meeting with Durham at New Road due to a shoulder problem.
Captain Vikram Solanki, who won promotion in his first year in charge will have prolific batsman Phil Jaques and England wicket-keeping prospect Steve Davies at his disposal though.
Left-handed Aussie all-rounder Doug Bollinger is set to play his first match in the county championship.
India spinner Murali Kartik makes his debut for Middlesex against Somerset at Taunton in Division Two of the LV County Championship.
Batsmen Nick Compton and Owais Shah return after their appearance for the MCC against Sussex at Lord's.
Middlesex are still without England's Andrew Strauss, Jamie Dalrymple, Ed Joyce, Ireland's Eoin Morgan and Sri Lanka's Chaminda Vaas because of the World Cup while seamer Chad Keegan is out with back trouble.
Former England seamer Richard Johnson faces his old county for the first time since his move at the end of 2006 while fellow winter signing seamer Tim Murtagh may also start.
Former Australia batsman Justin Langer will captain Somerset for the first time against his former county Middlesex.
England batsman Marcus Trescothick, in his first competitive match since returning early from England's winter Ashes tour, is expected to form a formidable opening partnership with Langer.
Neil Edwards is expected to be rewarded for his 212 against Loughborough with a starting place, while Australia all-rounder Cameron White flew in last night and should play.
Former England batsman Darren Maddy will make his LV County Championship for Warwickshire against Lancashire at Edgbaston after his winter move from Leicestershire.
England spinner Ashley Giles has suffered further hip problems and will be missing but Warwickshire include quick bowler Naqaash Tahir after an injury-disrupted 2006.
South Africa seamer Dale Steyn will make his first county championship appearance for Warwickshire but Sri Lanka wicketkeeper Kumar Sangakkara is still involved in the World Cup.
Batsman Paul Horton will bat at number five for Lancashire.
Lancashire have selected a squad of 12 but will be without the international trio of Muttiah Muralitharan, Brad Hodge and Andrew Flintoff who are representing Sri Lanka, Australia and England respectively at the World Cup in the Caribbean.
England seamers James Anderson and Sajid Mahmood are also missing on England duty but England A seamer Tom Smith is included alongside Oliver Newby.
Mark Chilton captains the side, who finished second in the championship last year, with former England all-rounder Dominic Cork set to continue.
England seamer Stephen Harmison has been named by Durham in their 12-man squad to travel to Worcestershire in Division One of the LV County Championship.
Harmison will be joined by his brother Ben, it could be the first time the pair represent Durham in the same match, and England A pace bowler Graham Onions.
Australia batsman and former Derbyshire player Michael Di Venuto will make his first appearance for Durham in a first-class match, as does Will Smith - following his move from Nottinghamshire.
Derbyshire will hand debuts to a trio of new players in the opening game of the LV County Championship Division Two against Essex.
Former Australia batsman Simon Katich will captain the side with former Gloucestershire batsman Phil Weston and Aussie all-rounder Ian Harvey also making their first starts.
Tom Lungley, Kevin Dean and Graham Wagg will provide the seam bowling options with Ant Botha in the spinning role.
Derbyshire will be missing their second overseas player, Australian batsman Travis Birt who is still recovering from ankle surgery.
Fast bowler Ian Hunter is also not yet ready for action after a knee operation and long-term injury victim all-rounder Graeme Welch is not expected to feature until August due to a calf problem.
Coach Dave Houghton said: "The first team of the season is always the most difficult one to pick because everyone has been working so hard during pre-season.
"The team I have picked - both batsmen and bowlers - is based entirely on the form that the players have shown in pre-season.
"It is important now that those not selected knuckle down in the second XI game against Lancashire to push the first team players for a place in the side."