Long before the 2012 Olympics, David Plummer had blocked off the dates of the London Games on his calendar. A lifetime of swimming had built him into a strong contender for the U.S. Olympic team, a goal he had been chasing since his days with the Gophers, and he anticipated the Olympic trials would stamp his ticket to the Summer Games.

Those plans changed when Plummer missed the cut by an unimaginably tiny margin: .12 of a second. With his agenda suddenly empty — and his future uncertain — he packed up his car and took off with his dog, driving around the country while the world watched the London Games. "It was very, very difficult not making the team," he said. "And I had a month with no plans. It took me a long time to process it."

Though that detour added some extra time to his journey, Plummer stayed the course. He has updated his destination — to the 2016 Rio Olympics, 365 days away — and now has a young son, a job as swim coach at Wayzata High School and new coaches and training partners at the U.

This week, Plummer returned to the world championships, where a 2013 silver medal in the 100-meter backstroke cemented his status as one of the world's fastest men in that event. The next 10 months will be devoted to filling a single gap in his résumé, one he has pursued for seven years.

"The Olympics is still the biggest thing in our sport," said Plummer, who finished ninth in the 100 back at the world championships Monday while recovering from a stomach ailment and will swim the 50 back on Saturday. "That's where we all want to be.

"It took a while to get over [missing the Olympic team in 2012], but it would be harder to walk away. I still feel so driven. I'm not ready to be done."

Training partners at the U

Plummer, 29, now trains at the U with Gophers head coach Kelly Kremer — who recruited him a dozen years ago — and assistant Gideon Louw. A 14-time All-America from 2005 to '08, the Oklahoma City native still holds six Gophers records, including marks in the 100 and 200 back.

Formerly based at the Minnetonka Swim Club, Plummer moved to the U after coach Ben Bartell left for Milwaukee in 2014. At the Jean K. Freeman Aquatic Center, he works out in a lively professional group with three former Gophers: fellow Americans Haley Spencer and Jared Anderson, and Josh Hall, a member of the Philippines national team.

Kremer has seen him grow from a young man with big ambitions to an accomplished, respected swimmer who was named a captain of the U.S. world championships team. Plummer's life also has prospered beyond the pool, since his 2012 marriage to former Gophers swimmer Erin Forster and the birth of their son, William, in 2013. While Plummer relishes his time caring for Will during Erin's medical fellowship, Kremer said Plummer's competitive edge has not softened.

"It's been awesome to watch David's development," Kremer said. "He continues to have such a love for the sport, and he's more driven now than he was going into the 2012 Olympics. He has unfinished goals, unfinished business. Missing out in 2012 lit a fire under him that brings him to the pool every day, ready to go."

A fraction of a second

Plummer still remembers that painful day at the 2012 Olympic trials in great detail. In his second year as a member of the U.S. national team, he needed to finish first or second in a highly competitive field in the 100 back to make the Olympic team.

He did not swim the first 50 meters with the control he wanted, hitting the turn in fifth place. "By the time I felt I was really coming on, it was too late," Plummer said. He touched the wall in 52.98 seconds, a crushing third-place finish after four years of work.

While Plummer took his dog, Wade, on the road trip, trials winner Matt Grevers and runner-up Nick Thoman went on to win the Olympic gold and silver medals. That helped Plummer realize that his effort had meaning and value. By pushing them so hard, he believed he helped to prepare them for the Olympics, a role that made him feel better the more he thought about it.

That was enough to keep him going, a decision that did not surprise his wife. "Knowing how much this means to him, I didn't think he would be done," she said. "And he is a very determined, very stubborn person."

Still driven to Olympic goal

The silver medal at the 2013 world championships gave Plummer a huge dose of confidence. Training with the group at the U — rather than solo, as he had before — also has been beneficial, putting him among other elite athletes as dedicated as he is. Plummer is in the water six days a week, sometimes twice a day, and works out in the weight room with Gophers strength coach Cal Dietz three times a week.

Stipends from USA Swimming and the New York Athletic Club have made it possible for Plummer to continue racing, even as a family man who will turn 30 in October. He said this is the best year of training he has had since 2012, and it has held other joys as well. Plummer's coaching career is thriving since he led Wayzata to its first state title in 2014, and Will already is splashing in the wading pool in their south Minneapolis neighborhood.

For the next 10 months, Plummer's calendar is packed with workouts, meets and the day-to-day details of training for the Olympics. But the pages for next August will be left blank, in the hope they will be filled with one word: Rio.

"It's going to take an amazing swim to make the team," Plummer said. "It's going to be tough. But there's just something about the Olympics; for all of us, that's the goal. That still drives me."