Entering the 2015 NASCAR season, Kyle Busch was a man in control. Among his sport's biggest stars, Busch was a hard-driving star from a car-racing family.

Then came Daytona. The crash. The injuries. The stretcher. The ambulance.

In a matter of seconds — the time it takes a car to skid off a racetrack, ramming into a concrete wall hood-first — the man so used to being in control had power over almost nothing.

"For me, the biggest decision was, in the middle of the night, do I want to get up and drag myself to the bathroom? Or just pee in this bottle here in bed?" Busch told Mashable seven months after the wreck, which left him with a broken leg and a broken foot on the 2015 NASCAR season's opening weekend.

"I didn't know if I would ever race again," he said.

Then came a grueling rehab and a furious racetrack comeback. Now Busch has a chance to do what seemed unfathomable during those long nights when he lay in bed, trying to decide where to pee: win the Chase for the Sprint Cup, NASCAR's Super Bowl.

Learning to walk again

Busch's life changed at Daytona International Speedway on Feb. 21. A teammate named Erik Jones lost control of his car. Several drivers were involved in the ensuing crash, but it was Busch's vehicle — he and Jones drive for Joe Gibbs Racing — that got hurtled out of the pack and off the track, on a beeline for that concrete wall.

Boom. Paramedics descended instantly. Busch's left foot was broken. So was his right leg. He felt that one right away. As paramedics tended to him on the ground, then put him on a stretcher and moved him into an ambulance, he knew he'd live. But he wondered if his career had ended there at Daytona.

Kyle Busch, and wife Samantha, after his crash at Daytona. Image: Courtesy Kyle Busch

Two surgeries followed. Later, a doctor told him to try to stand up for the first time. He couldn't.

"I just about passed out and had to go back down," Busch recalled.

Slowly, it got better. But each small step forward filled him with more drive to take the next.

"That was the biggest motivating factor," he said. "Being able to stand, then being able to walk, then do this, then this. You want to see that progression."

There were visitors, too, as he convalesced at home with pregnant wife Samantha watching over him. Other drivers. Friends. Family. Fans sent well-wishes by mail to the Joe Gibbs Racing headquarters. Some fans even sent cards to his home address; Busch doesn't quite know how they found it.

But the visitors and cards all added up. And helped, immensely.

"It was pretty constant," Bush recalled of the support. "No day ever felt too long."

Busch received a deluge of support while he recovered. Image: Courtesy Kyle Busch

Busch returned to the NASCAR circuit on May 16, finishing sixth at a race in Charlotte. He'd already missed the first 11 races of the Sprint Cup season, in which drivers seek to accumulate wins and points to qualify for the Chase for the Sprint Cup — a series of races that crown one ultimate champion.

One month later, at California's Sonoma Raceway, came a grueling competition that gave his still-healing foot its toughest test yet. But Busch won that race, giving a massive boost to his long-shot hopes of qualifying for the Chase for the Sprint Cup.

Busch was just getting started, though. He won again in Kentucky on July 11, then again the same month in New Hampshire. At the Southern 500 in South Carolina on the first weekend of September, he did what once seemed impossible by completing his furious comeback to qualify for the Chase for the Sprint Cup, which begins Saturday.

The story's still not over

Busch's number-18 car in action. Image: Nigel Kinrade/NKP via AP/Associated Press

Now here's Kyle Busch, just seven months after wondering if he'd ever race again, with as good a chance as anyone of winning NASCAR's biggest championship.

The Chase for the Sprint Cup's format is straightforward. Sixteen drivers qualify, then compete through a series of three elimination rounds. That leaves four drivers standing (or sitting). They go for glory in the championship race at Miami-Homestead Speedway on Nov. 22.

Busch still isn't 100 percent — "but I'm definitely in the 90s for sure," he said.

Even so, the plates and screws in his left foot can make walking around track facilities painful, even all these months later. (Racecar drivers actually have to do quite a bit walking while they're practicing, setting up, and doing basically everything else that isn't, you know, actual racing.) That's something other drivers don't have to deal with.

But Busch has no regrets. Up until that win in Sonoma, he never thought he'd be part of the field of 16 with a chance at winning the Chase for the Sprint Cup.

As for what lies ahead, Busch was matter-of-fact.

"We've won some races already," he said. "Now we've just go to win some races again."

After everything he's been through this year already, that doesn't sound so hard.