Now more than 250 points back, each driver's title hopes are realistically dashed -- for varying reasons and with varying consequences.
For Wallace, it was an ill-timed swoon that saw him finish 24th, 19th and 37th in a three-race span and fall from fourth to eighth in the standings. The result is that the legendary racer will retire after a season that will be remembered as admirable instead of unforgettable.
"We got down into turn one and the 66 spun out right in front of me," Wallace said of his shortened run Sunday at Atlanta. "I couldn't go low, and I couldn't go high. There was nothing else I could do. I saw the 37 car shoot high, and I saw the 66 spin. I was a car length behind them, and I was trapped."
The wreck came on the heels of tire and mechanical problems at Lowe's Motor Speedway and Martinsville Speedway.
"That's three in a row now," Wallace said. "It's absolutely unbelievable. I can't believe I came the whole season with no problems and right now at the very end it goes all to hell. This pretty well knocks us out [of the Chase]. I had a great car at [Lowe's] only to get in that deal. I had a great car last week at Martinsville only to have that problem there. It's hard to believe we came all year without any problems and now it's been three in a row.
Wallace was ever the professional even in the midst of his frustration -- happy just to go out after a top-10 season.
"We've had a real great run, and we've got three more races to have some more great runs," Wallace said. "We'll see what we can do. It's gratifying knowing I'm on top of my game. That's what I wanted to do. I'm just upset right now for what's happened the last three weeks. I've learned in my whole career that's racing. There's nothing you can do about it."
For Busch and Mayfield, the effective ends to their seasons came with varying degrees of certainty for the future.
Busch's title defense got off to a terrible start when he was wrecked in the first playoff event in New Hampshire. From that moment on, he's had mostly bad luck in the Chase.
"Roush Racing -- the 97 and before that the 17, and for that matter all five of our teams this year -- have had more good fortune than the average of our contemporaries," Busch's car owner, Jack Roush, said. "I knew we were gonna have to give some of that back and I feared that we'd have to give enough of it back that we would not be in the top 10 with more than one or two of our cars.
"Fortunately, we were able to carry that, so that meant to me that I got more than my share of good luck in the 26 races that preceded the Chase. Of course, now we're giving some more of it back."
Busch followed up a 35th-place finish at New Hampshire with a 23rd-place finish at Dover, Del. Then, after threatening to creep back into the action with an eighth-place run at Talladega -- on a day when some leaders faltered -- Busch followed up with a 14th-place run at Kansas on a day when the Chase leaders took the top seven spots.
Busch will race for Penske South in 2007 -- and perhaps ever earlier if a deal is struck -- and thus what these final three races mean to him is unclear.
What they mean for Mayfield and Co. is crystal clear, on the other hand. Mayfield, whose 38th-place finish Sunday dropped him to 10th in the standings, has emerged as a reliable contender, showing a propensity for finishing high in the first 26 races of the year and qualifying for the playoffs. What will happen now is a restructuring effort focused on finding a way to elevate the team's game come the final 10.
Mayfield wasn't willing to officially throw in the towel on Sunday, but the reality that it will take a near miracle did not escape him.
"I'm not sure exactly what the problem was," he said. "It's pretty wild because we never have problems like this, but it's going to happen every once in awhile. This team will keep digging. It might have cost us a chance at the championship, but we've got a long way to go.
"We'll keep working hard. This is part of it, it's part of racing. That's what happened to us last week. We cut a right front tire down. This week we had a little problem with the clutch or whatever."
Mayfield lamented the last two races in which a tire and a mechanical issue plagued the team. Still, the real reason for his spiraling playoff effort was the inability to rattle off top-10 and top-five finishes in the first five playoff events like the rest of the Chasers.
Nevertheless, the final three races of the season will provide him with the opportunity to begin the chemistry-building process for 2006 with shifting personnel. Mayfield's former car chief, Mike Shiplett, is helping Kenny Francis with chiefing duties. Other changes are also in store.
"We'll keep going," he said, "and do the best we can."
Rupen Fofaria is a freelance writer living in Chicago and a regular contributor to ESPN.com. He can be reached at firstname.lastname@example.org.