Day four of Royal Ascot is under threat after torrential rain hit the track.
Fans have to wait until 12.45pm to see whether the card, featuring two Group 1 contests, survives.
A total of 26mm of rainfall has fallen at the racecourse since close of play on Thursday, which turned the ground soft, heavy in places.
A statement from the track said: "Following 26 millimetres of rain since racing yesterday, and with a few false patches of ground which means the ability to race may be marginal, an inspection has been called for 12.45pm.
"We are also looking at options to re-align the rail to avoid these areas."
Betfair has odds of 1-2 about racing being abandoned and 13-8 that it will get the go-ahead.
If called off, it would be the first time the action has been lost since 1964.
The Commonwealth Cup (3.40pm) and Coronation Stakes (4.20pm) are the top level contests among the seven scheduled races.
Clive Cox has taken out his runners Supremacy and Diligent Harry from the first-named contest, while Primo Bacio is a non-runner in the latter.
Officials at Ascot are working on two contingency plans should the meeting fall to the weather.
The first one involves running a five-race card with the Coronation Stakes on the straight course, with the two lost races rescheduled for Saturday.
The second option would be to arrange a ten-race card tomorrow to include the Coronation Stakes, Commonwealth Cup and King Edward VII Stakes.
All of the action would be shown on ITV, with the following provisional order of running:
1.20pm Chesham
1.55pm Hardwicke
2.30pm Commonwealth Cup
3.05pm Coronation Stakes
3.40pm Diamond Jubilee Stakes
4.20pm Jersey Stakes
5.00pm King Edward VII Stakes
5.35pm Wokingham
6.10pm Golden Gates
6.45pm Queen Alexandra
