LAS VEGAS — Just as predicted, Dale Earnhardt Jr. and his team took a big gamble Sunday in hopes of winning another race.
This time they lost.
Earnhardt was leading on the last lap of the Kobalt 400 because his team opted not to bring his No. 88 Chevrolet into the pits for fuel during an earlier caution period.
But as he circled Las Vegas Motor Speedway the last time, the car ran out of gas on the back straightaway of the 1.5-mile track, enabling Brad Keselowski to shoot past him in his No. 2 Ford for the victory.
"It's very special to get a win early in the year," Keselowski said, noting that under new NASCAR rules, a win virtually assures a driver entry into the Chase for the Cup title playoff.
That was especially gratifying to Keselowski because, after the Team Penske driver won the series championship in 2012, he failed to qualify for the Chase last year.
The new format also gives regular-season race winners license to go for broke in other races until the Chase starts in September.
Earnhardt, after winning the season-opening Daytona 500 last month, said his Hendrick Motorsports team planned to do just that, and even Keselowski called their gamble Sunday "way out there."
"We weren't going to run in the top five [without] that particular strategy," Earnhardt said. "The gamble didn't pay off. We figured we were a lap short [on fuel]."
Earnhardt was asked if he and crew chief Steve Letarte would have gambled that way last year under the old rules, when collecting points was more paramount. "Absolutely not," Earnhardt replied.
Paul Menard finished third. Keselowski's teammate and race pole-sitter Joey Logano was fourth, Carl Edwards finished fifth and four-time Las Vegas winner Jimmie Johnson was sixth.
It was the 11th career win for Keselowski, who got his big break in NASCAR driving for Earnhardt's JR Motorsports team in NASCAR's second-level Nationwide Series.
Keselowski, 30, still races in the Nationwide Series for Penske, and he won Saturday's race here, giving him a Las Vegas sweep.
Several drivers besides Keselowski and Earnhardt took turns leading sizable chunks of the 267-lap race Sunday before the drama unfolded on the last lap. Kyle Busch led 52 laps before finishing 11th, and Logano led 44 laps.
When the race's final caution period occurred with 46 laps left, most of the leaders — including Keselowski — came into the pits for fuel. But a few did not pit so they could gain track position, including Earnhardt and Edwards.
When racing resumed, Earnhardt led Edwards and Keselowski was third. But as the laps wound down, Keselowski passed Edwards' No. 99 Ford and took aim at Earnhardt.
"Passing the 99 was a huge moment for us," Keselowski said. "That gave us an opportunity to really put pressure on Dale. I felt we could run him down."
Earnhardt, meanwhile, said that "once we got the lead it was like driving a Cadillac" because his car ran well without other cars disturbing the air in front of him. But he also had to conserve fuel when he could, enabling Keselowski to get within striking distance.
Earnhardt, 39, nonetheless has three top-two finishes in the season's first three races; he also finished second in last week's race at Phoenix.
He recalled another race several years ago when he ran out of fuel, then "bashed a fender on the car" in frustration.
Now, he said, "If we are smart and keep our composure, we've got a great opportunity this year to be this competitive every week."