England spinner Jack Leach has been ruled out of the men's Ashes with a lower back stress fracture.
The 31-year-old Somerset slow left-armer developed lower back symptoms during England's victory over Ireland in their one-off Test at Lord's this week.
Leach claimed four wickets during the 10-wicket win, bowling 20 overs in Ireland's second innings on Saturday.
A scan on Sunday in London revealed a stress fracture, which will keep him out of the forthcoming Ashes Test series which gets under way at Edgbaston on Friday 16 June.
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At statement released by the ECB said: "England will announce a replacement for the series in due course."
Leach has taken 124 wickets at an average of 34.18 in 35 Tests for England. In seven Ashes appearances, he has claimed 18 wickets at 35.05 apiece.
In the last series on home soil in 2019, Leach is fondly remembered for his 'heroics' with the bat and his one not out in the third Test at Headingley as part of a 76-run partnership with Ben Stokes, who smashed a stunning, match-winning 135.
Who are England's alternative spin options?
Leach has established himself as England's premier spinner under Stokes' captaincy and was the only specialist slow-bowler named in the 16-man squad on Saturday for the first two Tests.
The only other spinners to earn Test caps over that period are Rehan Ahmed and Matt Parkinson, as well as all-rounder options Will Jacks and Liam Livingstone.
Leicestershire 18-year-old leg-spinner Ahmed became England's youngest male Test debutant on the tour of Pakistan last winter, impressing with seven wickets at an average of 19.57, including a five-for.
Surrey off-spinner Jacks played two Tests on the same tour, taking six-for on debut. Livingstone also made his Test debut in Pakistan but was injured and did not bowl.
Parkinson came in as a concussion substitute for Leach in the Lord's Test against New Zealand last summer but the Lancashire leg-spinner has seemingly since fallen down the pecking order, being loaned to Durham earlier this season.
Hampshire left-arm spinner Liam Dawson and Nottinghamshire counterpart Liam Patterson-White could also come into contention as a more like-for-like replacements for Leach.
Panesar: I'd go with Ahmed to replace Leach
Former England spinner Monty Panesar, speaking to Sky Sports News:
"This is a massive blow for England because their plans were centred around Leach, who has been bowling superbly well over the last winter. He's been absolutely brilliant under the leadership of Brendon McCullum and Ben Stokes.
"They may just not even go with a [frontline] spinner for the first Test match, they may just stick with Joe Root and tell him to bowl 10 to 15 overs from one end to provide some control.
"They may just change the pitch conditions, go with slightly greener surfaces where all the England fast bowlers, especially the seam bowlers, are in the game throughout the whole Test match.
"I think I may go with Rehan Ahmed, that leg-spin option, and we have got Root to bowl off-spin. It's vital for England to have a spinner that is ready, especially in the back end of Test matches where the pitch will turn.
"England were thinking about Leach being that sort of guy who controlled one side of wicket and then the other side the bowlers can kind of rotate and be a bit more attacking.
"I am available! As an outside bet, I reckon that's 10,000-1 probably! I'm still sort of bowling and still playing around. If the opportunity came, I'll be ready for it."
Smith: Leach's injury leaves big shoes to fill
Australia batter, Steve Smith, said:
"I think it's a real shame for Leachy. He's done really well for England in the last 12-18 months, in particular. It's going to be some big shoes for them to fill. I feel for him, obviously he wants to be involved in the Ashes series. Hopefully, he recovers well."
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