Fleetwood needed to win the Nedbank Challenge in Sun City to wrap up the European Tour number one title and deny Rose and four other rivals, but fell short of that goal with a final-round 71 to finish in a tie for 10th in South Africa.
But that was enough for the 26-year-old to almost double his lead over Rose to 256,737 points, after the former US Open champion elected not to compete in the penultimate event of the season.
Four other players in Sergio Garcia, fellow Spaniard Jon Rahm and the English duo of Tyrrell Hatton and Ross Fisher are all but out of contention for the $1.25 million bonus prize.
World number six Rose only needs to finish sixth, if he is ahead of Fleetwood, in the 60-strong DP World Tour Championship field to secure the Race to Dubai spoils.
“Today when I knew I couldn’t win, I played the last few holes because you know every shot is going to count towards the end of the year,” said Fleetwood.
“If (you) start trying to look at it and do all the maths it’s going to do your brain in.
“I have a long flight with a lot of time to spend doing nothing and a lot more time doing nothing, as well.
“So, I’ve got to try and take my mind off it but it is what it is. I’ve played brilliant all year and to be in with a chance of winning the Race to Dubai, it’s pretty special, really.
“It’s not a burden. I don’t feel stressed about it. I don’t feel anxious. I just think it’s great that I’ve got the chance to win it, and a good chance.
“And as much as it depends on what they do, it is in my hands. I can take it out of everybody’s hands, but we’ll see.
“Coming down the back nine when I didn’t have a chance to win and kind of scrapping for my life on a few holes and a few shots, you do know every shot counts.”
Masters champion Garcia, who did not contest the Turkish Airlines Open or the Nedbank Challenge, will arrive in Dubai knowing mathematically he could win the number one title for the first time, but the 37-year-old would need both Fleetwood and Rose to finish near the bottom of the leaderboard.
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