David Plummer knocks off Aaron Peirsol in 100-meter backstroke

Aaron Peirsol started his career chasing down an icon, and he has spent the last decade or so at the top in this country, fending off threats in the 100-meter backstroke.

What finally knocked Peirsol off that high perch Wednesday night in Irvine, stunningly, was not a newcomer but someone who has been on the national scene for most of the decade. And not someone from a so-called swimming hotbed.

It was 24-year-old David Plummer, who wanted to be a firefigher as a kid growing up in Oklahoma City, went to the University of Minnesota and trains with the Minnetonka Swim Club.

Plummer touched out Peirsol at the wall, winning the 100 backstroke in 53.60 seconds for his first national title. Peirsol, the reigning world-record holder and Olympic champion who grew up in Orange County, was second in 53.63.

At least Michael Phelps and Natalie Coughlin kept a semblance of order in Irvine. She won the 100 backstroke in 1:00.14. Phelps won two races and promptly declared the second one, the 200 butterfly, a “terrible race” and said he felt “absolutely awful” during the event, which he won in 1:56.00.

On a scale of one to 10 in terms of fitness, he put himself at about a 5 1/2, maybe six. Bob Bowman, Phelps’ long-time coach, put it at four.

Imagine if Phelps had lost either race.

For the record, they were largely pleased with the first of the two wins, the 200 freestyle, which resulted in a stroke-for-stroke, crowd-pleasing duel with his longtime rival Ryan Lochte. Phelps finished in 1:45.61, the fastest time in the world this year, to Lochte’s 1:45.78.

The 200 butterfly, however, weighed more on his mind. Phelps seemed to become more critical the more he thought about it.

“That’s probably the worst 200 fly I’ve ever swam in my life,” he said. “In terms of strokes, turns, breathing off the wall. It’s weird because that’s the stroke I’ve felt the best in, all year long. To go out 56 flat is rather disappointing in my eyes.”

The two wins also put Phelps on the U.S. team for the Pan Pacific championships, which will be held in Irvine this month at the same venue as the nationals. Coughlin, by virtue of her win, is on the team, as is Allison Schmitt, who won the 200 freestyle in 1:56.84.

And now, Plummer.

“I made my first national team when I was 16, and that was eight years ago, the national junior team,” he said. “I’ve been working for a really, really long time and to have it pay off like this is huge. It means a lot to me.

“It does get cold in Minnesota. I don’t even know where to start. Being able to walk away with a gold medal against a field like that, it makes me think I can be the best in the world one day. That’s every swimmer’s dream. You can do it from anywhere. You don’t have to train next to the best in the world to be the best in the world.”

It was the first time Peirsol had lost in the final in the 100 backstroke at the nationals since he took fourth in the U.S. Olympic trials in 2000.

“I actually thought I was going to get him on the finish,” Peirsol said. “The finish was a little short.

Peirsol, who is equally classy in victory and defeat, mistakenly thought he and Plummer were the same age, but Peirsol is three years older.

“I’ve been swimming against Dave for 10 years now,” Peirsol said. “He’s always been very good. He’s always been one of those guys who had a very pretty stroke.”

lisa.dillman@latimes.com

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