Racing received a seismic jolt on Tuesday after Jockey Club Racecourses announced thatKempton, home of the historic King George VI Chase, could be closed for housing redevelopment "from 2021 at the earliest".
The track's owners, which operates 14 other racecourses in Great Britain, hopes to invest £500million into the sport in a 10-year plan - with the end of National Hunt and Flat racing at Kempton its most radical proposal.
The Jockey Club said in a statement that a request would be made to transfer the King George and a clutch of other big Kempton races to nearby Sandown.
And to fill the void left by the potential absence of a Flat track at Kempton, t he Jockey Club's land at The Links in Newmarket is the "front-running location" for a new floodlit all-weather circuit.
In partnership with housing contractor Redrow Homes, the Kempton estate has been submitted for consideration following Spelthorne Borough Council's 'Call for Sites' to address unmet local housing needs.
But the Jockey Club insists that Kempton will only be closed down if the move generates in excess of £100m investment and that the proposed all-weather circuit at Newmarket is given the green light.
Jockey Club senior steward Roger Weatherby said:"The decision to submit our estate at Kempton Park for consideration in the local plan is unique and has not been taken lightly.
"Our board of stewards are horsemen and, having carefully considered what we can achieve in the long-run from doing so, are unanimously of the view that British racing is better served by us doing so."
The King George VI Chase, staged each year on Boxing Day, is one of the great races in the jumps season.
Desert Orchid won the race four times before Kauto Star stunned the racing world with a fifth triumph in 2011. The two horses' ashes are buried by their respective statues at Kempton.
Sandown would be the chief beneficiary of the major investment, with plans in place to market it as "London's premier dual-code racecourse".
Kempton's other jumps fixtures could be spread around other Jockey Club-owned racecourses throughout the country, though consultation with the British Horseracing Authority and the wider sport would be needed.
Jockey Club chief executive Simon Bazalgette said : "We know there will some not happy, but we feel it is in the long-term interests of racing."
Bazalgette added that a new racecourse atNewmarket could become "Europe's best all-weather circuit, with all the facilities one would expect".
Redrow Homes said in a statement that the Kempton site could provide "circa 3,000 new homes".