The biggest summer in English cricket history gets underway on Friday as the county season starts in earnest. Surrey will be hoping to defend the crown they won in style last year, while Alastair Cook begins his post-international career at Essex. Sportsmail take a look at the runners and riders and pick out some players to watch this summer... Surrey will be defending their 2018 County Championship crown at the Oval this season Derbyshire Head of cricket: Dave Houghton Captain: Billy Godleman Overseas players: Logan van Beek (New Zealand), Kane Richardson (Australia, Twenty20) IN: Tom Lace (Middlesex, season loan), Mark Watt (Scotland, season loan) OUT: Ben Slater (Nottinghamshire), Will Davis (Leicestershire), Callum Brodrick (released), Hardus Viljoen (released), Gary Wilson (Ireland central contract) One to watch: Matt Critchley. A big season for the all-rounder, who scored in excess of 700 Championship runs and took 32 wickets with his leg-spin in 2018. Durham Lead performance coach: James Franklin Captain: Cameron Bancroft Overseas players: Bancroft (Australia), D'Arcy Short (Australia, Twenty20) IN: Alex Lees (Yorkshire), Ben Raine (Leicestershire), Jack Burnham (back from ECB ban), Ned Eckersley (Leicestershire) OUT: Paul Collingwood (retired), Barry McCarthy (Ireland central contract), Ryan Davies (released) One to watch: Jack Burnham. A second chance post-drugs suspension for a young player to fulfil the talent that saw him break the England' record for runs at an Under-19 World Cup three years ago. Essex Head coach: Anthony McGrath Captain: Ryan ten Doeschate Overseas players: Peter Siddle (Australia), Adam Zampa (Australia, Twenty20) IN: Cameron Delport (Leicestershire) OUT: James Foster (retired), Ashar Zaidi, Callum Taylor, Matt Dixon (all released) One to watch: Sir Alastair Cook. Not a lot to prove but a lot to give, the former England captain starts a three-year commitment to the county game. Alastair Cook returns to the fold at Essex after calling time on his international career Glamorgan Interim head coach: Matthew Maynard Captain: Chris Cooke Overseas player: Shaun Marsh (Australia) IN: Billy Root (Nottinghamshire), Charlie Hemphrey (Queensland) OUT: Aneurin Donald (Hampshire) One to watch: Charlie Hemphrey. Englishman, Sheffield Shield winner, and now - at the belated age of 29 - county cricketer. Gloucestershire Head coach: Richard Dawson Captain: Chris Dent Overseas players: Dan Worrall (Australia), Michael Klinger (Australia, Twenty20) IN: Stuart Whittingham (Sussex) OUT: Liam Norwell and Craig Miles (both Warwickshire), Kieran Noema-Barnett (released) One to watch: Matt Taylor. Younger brother of Jack, the left-arm fast bowler has a chance to step up as attack leader across all formats. Hampshire Head coach: Adrian Birrell Captain: James Vince Overseas player: Aiden Markram (South Africa) IN: Donald (Glamorgan), Keith Barker (Warwickshire), James Fuller (Middlesex) OUT: Jimmy Adams, Sean Ervine (both retired), Calvin Dickinson, Asher Hart, Reece Topley, Chris Sole (all released) One to watch: Vince. Will open the batting, at the behest of England selector Ed Smith, as the scrimmage for Ashes places takes shape. Kent Head coach: Matt Walker Captain: Sam Billings (Heino Kuhn will deputise while Billings at IPL) Overseas players: Matthew Renshaw (Australia), Adam Milne (New Zealand, T20), Mohammad Nabi (Afghanistan, T20) IN: Matt Milnes (Nottinghamshire), Fred Klaassen (Netherlands) OUT: Will Gidman, James Tredwell, Matt Hunn (all retired) One to watch: Grant Stewart. Australian-raised player who has impressed with both bat and ball in short first-class career to date. Lancashire Head coach: Glen Chapple Captain: Dane Vilas Overseas players: Joe Burns (Australia), James Faulkner (Australia, T20), Glenn Maxwell (Australia, CC/T20 split) IN: Richard Gleeson (Northamptonshire) OUT: Jordan Clark (Surrey), Arron Lilley (Leicestershire), Simon Kerrigan, Karl Brown (both released) One to watch: Haseeb Hameed. Once destined to reign at the top level, the three-cap Test opening batsman enters the final year of his contract, having averaged single figures in last year's Championship. Leicestershire Head coach: Paul Nixon Captain: Paul Horton Overseas player: Mohammad Abbas (Pakistan) IN: Davis (Derbyshire), Lilley (Lancashire), Chris Wright (Warwickshire), Hasan Azad (ex-Loughborough University) OUT: Raine (Durham), Delport (Essex), Zak Chappell (Nottinghamshire), Michael Carberry, Eckersley, Richard Jones, Mark Pettini, Rob Sayer, Tom Wells One to watch: Tom Taylor. Former Derbyshire seamer will get opportunities following the departures of Raine and Chappell. Middlesex Head coach: Stuart Law Captain: Dawid Malan Overseas players: AB de Villiers (South Africa, T20), Mujeeb Ur Rahman (Afghanistan, T20) IN: None OUT: Fuller (Hampshire), Nick Compton (retired), Ravi Patel (released) One to watch: Toby Roland-Jones. The England international is fit again after missing 18 months of cricket through injury. Northamptonshire Head coach: David Ripley Captain: Alex Wakely Overseas players: Jason Holder (West Indies, April), Temba Bavuma (South Africa, May 14-July 17), Faheem Ashraf (Pakistan, T20) IN: Blessing Mazurabani (Kolpak), Ben Cotton (was on summer contract) OUT: Ben Duckett (Nottinghamshire), Gleeson (Lancashire), Steven Crook (retired), Gareth Wade (released) One to watch: Josh Cobb. Remains one of the next-best English cricketers in white-ball formats, and the 50-over competition begins in a fortnight. Nottinghamshire Head coach: Peter Moores Captain: Steven Mullaney Overseas players: James Pattinson (Australia, April 17-July 11), Dan Christian (Australia, T20) IN: Joe Clarke (Worcestershire), Chappell (Leicestershire), Duckett (Northamptonshire), Slater (Derbyshire) OUT: Milnes (Kent), Will Fraine (Yorkshire), Root (Glamorgan), Riki Wessels (Worcestershire), Ben Kitt (released) One to watch: Zak Chappell. Half of the 18 counties expressed an interest in signing the towering seamer despite a career return to date of just 38 first-class wickets. James Vince is set to open the batting for Hampshire as he eyes an England recall Somerset Head coach: Jason Kerr Captain: Tom Abell Overseas players: Azhar Ali (Pakistan), Jerome Taylor (West Indies, T20) IN: Jack Brooks (Yorkshire) OUT: Johann Myburgh (retired) One to watch: Tom Abell is the youngest county captain on the circuit and, following a tough baptism, an increasingly impressive one. Surrey Head coach: Michael Di Venuto Captain: Rory Burns Overseas players: Dean Elgar (South Africa), Aaron Finch (Australia, T20) IN: Liam Plunkett (Yorkshire), Jordan Clark (Lancashire) OUT: Mat Pillans (Yorkshire) One to watch: Jamie Smith. Only 18 but already a first-class centurion, the latest wicketkeeper-batsman off the Oval production line can expect several opportunities at number six between the comings and goings of Surrey's England contingent. Sussex Head coach: Jason Gillespie Captain: Ben Brown Overseas players: Mir Hamza (Pakistan), Rashid Khan (Afghanistan, T20) IN: None OUT: Whittingham (Gloucestershire) Warwickshire First-team coach: Jim Troughton Captain: Jeetan Patel Overseas players: Patel (New Zealand), Ashton Agar (Australia, T20) IN: Miles and Norwell (both Gloucestershire) OUT: Barker (Hampshire), Josh Poysden (Yorkshire), Wright (Leicestershire), Grant Elliott, Jonathan Trott (both retired), Boyd Rankin, Sunny Singh, Andy Umeed (all released) One to watch: Henry Brookes. A proper fast bowler, with an excellent Yorker and mature beyond his teenage years. Worcestershire First-team coach: Alex Gidman Captain: Joe Leach Overseas players: Callum Ferguson (Australia), Martin Guptill (New Zealand, T20) IN: Wayne Parnell (Kolpak), Wessels (Nottinghamshire) OUT: Clarke (Nottinghamshire), Steve Magoffin (retired) One to watch: Pat Brown. A stress fracture of the back restricted his winter exploits but eyes will be on him following his 31 Twenty20 wickets in 2018. Yorkshire Head coach: Andrew Gale Captain: Steven Patterson Overseas player: None IN: Fraine (Nottinghamshire), Duanne Olivier (Kolpak), Poysden (Warwickshire) OUT: Brooks (Somerset), Lees (Durham), Plunkett (Surrey), Azeem Rafiq, James Wainman (both released), Andrew Hodd (retired) One to watch: Harry Brook. Makes batting look effortless at times but also has a tendency to get out softly, and as such averages only in the low 20s in four-day cricket. Sportsmail predictions County Championship winners: Nottinghamshire Runners-up: Surrey Relegated: Kent Promoted: Middlesex, Lancashire, Sussex 50-over champions: Surrey Twenty20: Gloucestershire FIVE TO WATCH Duanne Olivier (Yorkshire) Caused a huge stir by turning his back on South Africa at the peak of his powers to join Yorkshire as a Kolpak signing and an even bigger one by telling Sportsmail he wants to serve a three-year qualification period and play for England. The bottom line is, fitness permitting, that he should take plenty of wickets but it is myopic of Yorkshire to sign him as a non-overseas and it would make a mockery of international cricket if England ever considered him. Ben Duckett (Nottinghamshire) No-one doubts his explosive talent, even if his technique was exposed by spin when he toured India and Bangladesh, but the question marks have always been over his attitude. Now, slimmed down and with a new county in Notts who specialise in proving England with players, Duckett starts the season with the slate clean, Trevor Bayliss name-checking him during the winter as a candidate to open the batting again in Test cricket. Will Jacks (Surrey) The latest exciting talent to come off the Surrey conveyor belt, Jacks exploded into public consciousness with an extraordinary century off just 25 balls in a pre-season 10-over game against Lancashire in Dubai last month. Made his debut at 19 in all three formats during Surrey's Championship winning season last year while his off-spin marks him as a genuine all-rounder. Could be the best of all the young hopefuls at the Oval. Liam Livingstone (Lancashire) Something of a false start as an England player but only lost his place in the Test squad through injury and remains a rare talent in white and red-ball cricket. Highly regarded by new Test batting coach Graham Thorpe and should be better for giving up the Lancashire captaincy that seemed to affect his form last year. Able to deliver both leg and off-spin too depending on whether he is bowling to right or left handers. Sir Alastair Cook (Essex) Essex have the considerable boost of their knight being available all season after confirming his international race really is run despite telling Sportsmail 'never say never' in February. Bottom line is he only ever meant that he would make himself available again in an emergency because he could never turn his back on his country. It won't happen. Instead he has a smile on his face and will be filling his boots at Chelmsford. Enjoy him while you can. All rights reserved for this news site dailymail and under his responsibility