A victory for SwedenÃ¢â‚¬â„¢s Peter Hanson at the Czech Open on Sunday has seen Casey drop out of the standings for automatic qualification.
Casey has no chance of getting back into the top nine as he will be absent from the final qualifying event at Gleneagles this week.
HansonÃ¢â‚¬â„¢s triumphed at the second play-off hole to push himself into 8th place in the points table, just in front of SpainÃ¢â‚¬â„¢s Miguel Angel Jimenez.
Past Ryder Cup players Luke Donald, Padraig Harrington and Justin Rose will also be missing from the final qualifying event, with all of them sitting outside the top nine.
Promising Italian Eduardo Molinari is also outside the qualifying places meaning that Captain Monty will be forced to leave at least two big name players behind.
Meanwhile, Englishman Simon Dyson and SpainÃ¢â‚¬â„¢s Alvaro Quiros could still book their places automatically if either of them were to win at this weekÃ¢â‚¬â„¢s Johnnie Walker Championship, while a top-two finish would Ross McGowan would also be good enough.
It should prove to be a fascinating week.
MORE: The latest football news
MORE: The latest tennis news
BIOGRAPHY: Anthony Martial