Pole-sitter Jimmie Johnson led a race-high 172 laps, but never after lap 228 of the regularly scheduled 267, as Keselowski captured his first victory in a Chase race and switched places with previous Chase points leader Denny Hamlin of Joe Gibbs Racing, who dropped from first to third in the standings.
On a day in which seven of the 12 Chase qualifiers changed places in the standings, the Kansas City-area's Clint Bowyer started ninth, finished 10th, but actually moved up in the points' standings from sixth place going into the Chicagoland race into a tie for fourth with Kasey Kahne and Hamlin.
Things may have been far from disastrous for Bowyer and his No. 15 5-Hour Energy Michael Waltrip Racing crew, but the 33-year-old native of Emporia, Kan., was not happy with his performance in the first of the 10 races that will determine this season's Sprint Cup Series champion.
"It just wasn't a good day," said Bowyer, who is competing in his second Chase in the past three years. "I don't know whether it was strategy or pit stops or what, but it seemed like we lost spots on pit road all day and it just cost us.
"You ain't going to win a championship with decent days - you have to have good days," he said in his post-race comments after the Geico 400 Sunday at Chicagoland Speedway's 1.5-mile tri-oval track.
The win on Sunday was Keselowski's fourth Cup victory of the 2012 season, tying him with Hamlin for the most wins this year. Five-time Cup champion Johnson and defending-champion Tony Stewart both have three wins so far this season.
"It feels like round one of a heavyweight title bout," Keselowski said. "It's a 10-round bout. Week one's done. We might have won the (first) round, but we didn't by any means knock ‘em out. We have a lot of work (still) to do."
The driver of the No. 2 Miller Lite Dodge for Penske Racing. Keselowski also achieved another first in his career by winning the first Chase race on Sunday at Chicagoland: It marks the first time he has held the points lead in NASCAR's top racing series.
Round two in the 2012 Chase for the Sprint Cup is Sunday at New Hampshire Motor Speedway. This is the second Sprint Cup race in New Hampshire this season. Kahne won the first race there this year in mid-July.
Stewart won the second of his five Chase victories at the one-mile flat track in Loudon, N.H., and along with fellow Chasers Gordon and Johnson has won three times in his career at New Hampshire. Bowyer also has experienced some success at New Hampshire, recording two of his seven career wins there and four top-10s in 13 starts.
Five other notable takeaways from Chase race No. 1 at Chicagoland Speedway:
- Tony Stewart's sixth-place finish (after starting 29th) was his first top-10 finish in the last six races this season.
- A driver in the Chase has won all nine of the opening races since the inaugural Chase for the Cup was held in 2004.
- Eleven of the 12 Chase qualifiers this season finished in the top 18 at Chicagoland on Sunday. Jeff Gordon, the final driver to qualify in this year's Chase field, finished 35th out of the 43-car field on Sunday after crashing into the Turn 1 wall when the throttle stuck in his No. 24 Chevrolet two-thirds through the race.
- This is the fourth time in 16 Chase races that Jimmie Johnson has led for over 100 laps and not won the race.
- Brad Keselowski is the 21st different driver to win a Chase for the Cup race.
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