INDIANAPOLIS -- On the surface, the International Race of Champions series is certainly competitive enough, but the four-race quest for the eventual championship doesn't quite have the pressure-filled environment that trying to win a Winston Cup or Indy Racing League or CART title holds.

Yet at the same time, Saturday's finale of the 27th IROC season could prove to be a microcosm of greater things to come for Winston Cup driver Kurt Busch. For, while he finished fourth in the fourth and final race of this season, Busch earned enough points to win his first overall IROC championship in his first year of competing in the series, edging Mark Martin, Jimmie Johnson and Mike Bliss.

"I've won local championships, I won a Featherlite Southwest series championship, which was big in 1999. Winning my first ever Winston Cup race, this is a parallel of those two, and being able to be a champion once again," said Busch, who becomes the seventh rookie to win the IROC title, joining Mark Donohue (1974), Harry Gant (1985), Al Unser Jr. (1986), Geoff Bodine (1987), Ricky Rudd (1992) and Kevin Harvick (2002).

"Championships are few and far between," Busch said. "This is something I worked very hard to achieve and something that ranks right up with my first Winston Cup win."

Added Martin, Busch's teammate at Roush Racing, "Kurt was just awesome. Every race, he was right there. It would have been more fun if we had won (the title). That's what we were after, but Kurt was just incredible this year."

Indeed, Busch seemed to be made to drive in the IROC series. In much the same way he's maintained his ranking in the top-10 for most of this season thus far on the Cup side of things, Busch used consistency to take the IROC title -- and made it look easy doing so. He finished second in the season-opener at Daytona, won at Talladega, was third at Chicago and wrapped things up with his season "worst" fourth-place finish at the legendary Indianapolis Motor Speedway.

"It's quite an honor and a good day, particularly since we qualified sixth in our Winston Cup car," Busch said. "One bad finish will take you out of the IROC series championship. It was great to bring it home. I achieved the best finishes I possibly could."

While Busch was the effusive target of Martin's praise, being teammates in Winston Cup means nothing when the 12 regular competitors get behind the wheel of the equally prepared IROC Pontiac Firebirds. It's every man for himself in each race, each lap.

"There are no teammates in IROC," Busch said. "You have got to go. This is a 40-lap venue where you just have to go every lap and what it needed to be, and we were able to go away with the top spot today."

World of Outlaws star Danny Lasoski, whose boss is one of Busch's chief rivals on the Cup circuit, Tony Stewart, finished ninth in the final IROC standings in his first season, but he's quickly become a convert to that style of equal racing, where the driver's overall talent is the usual common denominator between winning and being an also-ran.

"This is the greatest series I've ever been in in my life," Lasoski said. "It's a heck of a challenge to come off dirt on here. … I tell you what, I pray to God they invite me back next year, because I'll be the first one here."

Busch earned $250,000 for taking home the IROC title. And as has been the case in most of the series' 27-year run, Winston Cup drivers dominated the rankings. In fact, the first three IROC season leaders (Busch, Martin and Saturday's race winner, Jimmie Johnson) and six of the first seven (Harvick finished fifth, Ryan Newman was sixth and Greg Biffle was seventh) were Winston Cup drivers. The seventh was from the Craftsman Truck Series (Mike Bliss, who finished fourth).

Rounding out the final standings from eighth to 12th place were IRL driver Sam Hornish, Lasoski, IRL drivers Felipe Giaffone and Scott Sharp (who replaced the injured Giaffone in the series), World of Outlaws driver Steve Kinser and IRL pilot Helio Castroneves.

Saturday's race appeared to be Castroneves' for the taking. He led the first 20 laps. But after a restart on lap 21 due to a caution flag being thrown for debris on the racetrack, Castroneves got caught in Johnson's draft, falling quickly from first to seventh. The former Indianapolis 500 winner eventually finished a disappointing eighth.

"I just need to know how to find the draft," Castroneves said. "Those guys, side-by-side, I don't know how they do it. Harvick was just pushing Jimmie like crazy (on the restart) and I was thinking, 'How is this possible?' It was fun. Unfortunately, I think I destroyed the right front tire. I was feeling like a pro for a moment, thinking, 'Hey, I'm not doing that bad,' but those guys have a lot of experience. I'd like to learn more."

Johnson won the race with an average speed of 135.287 mph, beating Harvick to the finish line by .697 of a second.

"It's an honor to be here and win at the Brickyard," Johnson said. "It's something I've dreamt of doing, and hopefully this is a good sign of things to come (Sunday) for our race team in the Winston Cup Series. I knew (passing Castroneves on the restart) was going to be my only opportunity to get a pass done.

"When the caution came out I knew I would have about a lap to get something done. Harvick helped me down the straightaway and helped me get by, and it helped him into second place, so that was it from there."

Jerry Bonkowski covers NASCAR for ESPN.com. He can be reached at Motorsportwriter@Yahoo.com.