RIO DE JANEIRO – Considering how long it took David Plummer to get to the Olympics, he doesn't mind a few more days of discipline.

The former Gophers swimmer won't indulge in any Olympic festivities until he has swum his final stroke in Rio. That means a visit to Copacabana Beach or cheering at a basketball game will be delayed until after the men's 100-meter backstroke, which begins Sunday with the morning preliminaries and evening semifinals.

"At this point, it's all about the race and getting ready to compete,'' said Plummer, of Minneapolis. "All the spectacle and excitement outside the pool, that can wait until later.''

If all goes as planned, Plummer won't see anything outside the Olympic Village and the Olympic Aquatics Stadium until Tuesday, the day after the 100 back finals. He enters the Rio Games with the fastest time in the world this year — 52.12 seconds, swum in the semis of the Olympic trials in June—but has a swift school of sharks at his heels.

U.S. teammate Ryan Murphy edged Plummer to win the event at the Olympic trials and is a fast-developing prodigy. Australian Mitch Larkin won world championships last year in the 100 and 200 backstrokes. Frenchman Camille Lacourt was fourth at the 2012 Olympics in the 100 back and is tied with Larkin as the third-fastest performer of all time in that event.

Plummer already has scored one breakthrough. After missing the 2012 Olympic team by .12 of a second, he followed a great 2015 season with another move forward this year, leaving him confident he has more to give.

"It's going to be very competitive,'' said Plummer, who trains at the U with coaches Gideon Louw and Kelly Kremer. "But everything is going really well. I feel great. I'm ready.''

After the trials ended in early July, the U.S. team held training camps in San Antonio and Atlanta. During the Atlanta camp, they held late-night practices and were told to stay awake until at least 1 a.m. to simulate the timing of the Olympic meet. The swimming finals begin at 10 p.m. Rio time.

The team also created a "Carpool Karaoke'' video, riffing on the singing-in-the-car segment created by late-night TV host James Corden. In the video, which can be viewed at www.usaswimming.org, Plummer rides with fellow Olympians Katie Ledecky, Anthony Ervin, Kelsi Worrell and Molly Hannis. The group belts out the theme to "That '70s Show'' while mimicking the show's opening, in which the people in the car keep changing seats.

Plummer said the serious side of the camps went very well, too. He is fine-tuning his stroke to try to shave a few hundredths of a second where he can, knowing every fraction will be necessary to help the U.S. continue its Olympic dominance in the men's 100 back. American swimmers have won the past five Olympic golds in the event and have gone 1-2 in the past two Summer Games.

At the Olympic Village, Plummer is rooming with a star-studded group including Michael Phelps, Ryan Lochte, Conor Dwyer, Jimmy Feigen and Chase Kalisz. Though he's all business for the moment, that doesn't mean he isn't enjoying every second of his time in Rio.

"I keep having moments where it seems real, and then it doesn't seem real,'' he said. "I absolutely appreciate this experience, to be part of the U.S. Olympic team.''