While Northern Ireland's Graeme McDowell took the ultimate honours at Le Golf National, Warren managed to grimly hold on to the final Muirfield place on offer from the European Tour's mini order of merit.
The leading five players in the top 20 of the Race to Dubai, who were not already exempt into the third major of the season, would qualify at close of play yesterday. Richard Sterne, who finished runner-up to McDowell in Paris, Brett Rumford, Miko Illonen and Thomas Bjorn took the first four spots, while Warren edged out fellow Scot Stephen Gallacher by just €888 with earnings of €517,494. He moved up to 17th on the money list, a single place ahead of Gallacher, despite finishing behind him on the French Open standings.
Warren, two-time Tour winner, had been just two strokes off the pace after covering his first 10 holes in three under par, but his challenge petered out on Le Golf National's robust closing stretch. Warren made bogey at both the 13th and 14th, double-bogeyed the 15th and leaked another shot on 16 in a two-over 73 which dropped him into a tie for 13th place on 284, level par.
Gallacher, meanwhile, signed off with a 70 for 283 to share eighth, but the Bathgate man will now have to win this week's Scottish Open if he wants to join the Scottish contingent at Muirfield.
At the head of affairs yesterday, McDowell carded a closing 67 for a nine-under total of 275 and eased to a four-shot win over South African Sterne, who had been only one behind until bogeys at the 16th and 17th scuppered his title bid.
McDowell, who has now won three times in a roller-coaster season, missed the cut in last week's Irish Open but reaped the rewards of staying on at Carton House over the weekend to work on his game. The first prize of €500,000 took him to within less than €30,000 of Justin Rose at the top of the tour's Race to Dubai.
"It's very special after the last couple of months," McDowell admitted. "It's been a funny year. My game has not felt far away most weeks but I have missed a lot more cuts than normal, and missing cuts hurts. It certainly motivated me a lot the last few weeks."
One behind at the turn, McDowell holed a nine-footer for birdie on the 10th to move into a tie at the top and inched ahead on the 12th as Sterne leaked his first shot of the day.
Luck certainly appeared to be on the Northern Irishman's side as he pulled his tee shot on the 16th but saw the ball take a fortunate bounce away from the heavy rough and kick 90 degrees right to leave a relatively simple up-and-down.
Sterne had called for a "G-Mac bounce" after also pulling his tee shot but was not so fortunate and a bogey 4 gave McDowell a two-shot lead with two to play. He made certain of victory with a superb birdie on the 17th.
Scott Henry, the Clydebank rookie, tied for 29th on 287 while Chris Doak and David Drysdale both finished on the 290 mark.