In the early weeks of the season, a number of England seam-bowling candidates with either international experience or the potential for a call-up by the new selection panel are already unavailable through injury. With input from Kevin Shine, the ECB's lead fast bowling coach, we look at those on the treatment table and when some might be back in contention.
Toby Roland-Jones
Out for the season due to a recurrence of the stress fracture diagnosed at the end of the 2017 domestic season. The ECB's view is that, in an ideal world, Roland-Jones might have spent the whole winter recovering and rehabilitating from the stress fracture. But, such was his desire to play a part in the Test team, he asked to play for the Lions and subsequently suffered more pain in his back after starting the season for Middlesex.
Kevin Shine: "Listening to the player is of paramount importance and we were optimistic that [he] would recover in time."
George Garton
Garton impressed the England management with his pace at a net session and was briefly drafted into the Ashes squad after a series of injuries to more senior bowlers. Aged just 21 and with nine first-class games behind him, he is raw - he has been known to deliver the odd beamer - but he was recently namechecked by Mick Newell (still, for now, an England selector) as one they might have picked had he been fully fit. Currently recovering from a side injury sustained as he lifted a case off a luggage carousel, he has recently played 2nd XI cricket and should be available for selection by Sussex soon.
Shine: "This is a very frustrating injury for everyone given George's obvious potential."
Olly Stone
Started the season in eye-catching fashion with an eight-wicket haul against Sussex. Currently sidelined after sustaining an injury during warm-ups for the following game, he is expected to return in the next couple of weeks. His director of cricket at Warwickshire, Ashley Giles, urges caution and patience over Stone's England aspirations but such is his ability that the chance could come sooner than anticipated.
Saqib Mahmood
Toured with England Lions and was involved in the North v South games, but has subsequently suffered a minor groin injury, missing Lancashire's opening three fixtures.
Shine: "Hopefully he'll be bowling again very soon. It's good that he has to compete to get in a very strong side. He is different from many fast bowlers, with his skiddy trajectory and ability to reverse swing the ball."
Jamie Overton
The selectors, impressed by a couple of hostile spells and the obvious potential, were keen to include him in their Ashes squad, but were thwarted by a recurrence of back trouble. He has since suffered a side injury, after bowling with a remodelled action, and hasn't played a first-class game since June.
Shine: "Jamie is a bowler of high potential. He has been bowling since September. The plan, in collaboration with Somerset, was to allow his body time to adapt to the technical changes. We all know that there are no guarantees for ongoing fitness - a good example of this is [Australia's Mitchell] Starc, [Pat] Cummins and [James] Pattinson, who are all now injured - but we will continue to leave no stone unturned regarding training and injury prevention."
Steven Finn
Sustained a "minor ligament strain" in his right knee while playing in the Pakistan Super League. It is not related to the injury in his left knee that ended his Ashes tour and necessitated surgery. He is expected to appear for Middlesex again soon.
Zak Chappell
The record may be modest - he has a bowling average in excess of 50 - but such is Chappell's obvious potential that both Nottinghamshire and Warwickshire have now made 28-day approaches with a view to luring him from Leicestershire. He is currently recovering from a groin injury, but recently played for the seconds as a specialist batsman and bowled four overs in one game.
Shine: "We need to manage expectations around him, be patient and we will have a very exciting cricketer for the future."
Reece Topley
After a succession of stress fractures in his lower back, Topley decided to concentrate on white-ball cricket in 2018. He retains hopes of returning to red-ball cricket if he can overcome his injury issues. Topley has shown promise since breaking through as a teenager and may come again.
Shine: "Hampshire, ECB and Reece collectively decided that to give his body time to get stronger he should just play white-ball for the 2018 season. This allows us to put in place a programme which gives Reece time to recover from matches, train and make sure his technique is as good as it can be."
George Scrimshaw
Yet to play a first-class game, so perhaps unlikely to enter selection discussions, Scrimshaw is currently struggling with injury having sustained a stress fracture during the 2017 season. He attended the ECB's pace programme over the winter and Worcestershire are hoping he will be able to play in June.
Shine: "Being patient with George will be the key. He's 6ft 7in and has a young bowling history. He was 19 when he started the programme this year."

George Dobell is a senior correspondent at ESPNcricinfo