This time she finishes, but it still isn’t Danica Patrick’s day

Not that there was any doubt, but Danica Patrick learned for herself Saturday that big league stock-car racing isn’t easy.

That was evident as Patrick, the IndyCar Series star who’s trying her hand at NASCAR, clearly was perturbed after finishing 31st among 43 cars in the Stater Bros. 300, a race in NASCAR’s second-tier Nationwide Series at Auto Club Speedway in Fontana.

Patrick, 27, accomplished one goal by finishing the race, her second after her NASCAR debut a week ago at Daytona International Speedway was cut short when she was caught in a multi-car crash just past the halfway point.

But she trailed the top 30 cars for much of the day and ended Saturday’s race three laps behind winner Kyle Busch, the reigning Nationwide champion who won the race for the second consecutive year by passing Greg Biffle on the final lap.

“I’m a competitor and I want to run up front and I’ve gotten used to running up front and so it’s an adjustment, it’s like starting from zero again,” said Patrick, who is racing part time in NASCAR around her full IndyCar schedule this year.

The race “obviously wasn’t what we wanted, we don’t want to finish a few laps down,” she said. “When I came here today I just said I wanted to finish, and the expectation of staying on the first lap [with the leaders] was probably not realistic, and I knew that.”

Patrick got off to a poor start, with her No. 7 JR Motorsports Chevrolet being lapped by the leaders only 18 laps into the race on the two-mile Auto Club Speedway oval.

On Lap 35 she was penalized for speeding as she left pit road, and by Lap 60 she was lapped again by the leaders. She got a second pit-road speeding ticket on Lap 79, although some experienced Nationwide drivers such as Carl Edwards made a similar mistake.

But Patrick also made some progress. Her lap times improved from the start even as she had to adjust to changes in the Fontana track.

“I learned what happens with the track from the beginning to the end of a race,” she said. “The track tightened up, it picks up a lot of grip, so you have to be prepared for that.”

Patrick was expected to have a handful at Fontana.

Unlike the high-banked Daytona speedway, where the cars draft in bunches and drivers seldom ease off the throttle, the Fontana track requires different skills as drivers maneuver their 3,000-pound stock cars through its relatively flat corners.

Auto Club Speedway, in fact, is a better example of the tracks where NASCAR mostly races -- “the bread and butter,” as Patrick’s crew chief, Tony Eury Jr., called them -- and thus was essential to Patrick’s NASCAR education.

“I was hoping I could finish in the top 20,” Eury said. “We were a little off. I’ve seen a lot of people [do] a lot worse. I’m proud of her, she learned a lot, she did really well.”

But Eury acknowledged that, inexperienced or not, Patrick didn’t take kindly to finishing so far back. “Results are everything for her,” he said. “She’s a great race car driver and we picked her for a reason.”

Patrick’s long day started in the morning when she qualified only 36th with a speed of 172.990 mph, about 8 mph slower than that of the pole-sitter, Joey Logano.

“We gained a lot of speed from the time the race started to the end,” Eury said. “That’s what we came here to do. Everybody’s just got to give her time.”

Patrick said she has to be realistic about her progress.

“This is a whole new ball of wax for me and it’s all different,” she said. “I have to disconnect from the results for quite some time, I think, because they’re probably not going to be what I’m used to.”

james.peltz@latimes.com