Just minutes after Lilly King qualified for the 200-meter breaststroke during the US Olympic Team Trials in Indianapolis on Thursday, longtime boyfriend, James Wells, surprised her backstage with a heartfelt marriage proposal and a diamond engagement ring. And best of all, the moment was captured live during NBC's coverage of the event.

"Getting to watch you over the last four years, both in and out of the pool, and just to see you grow has been so awesome," Wells told King, who was still in her swimsuit and dripping wet.

"I don't regret for a minute dropping my job and moving halfway across the country for us to move in together," he continued. "It has been awesome, and I am very excited to see where this is going. So, dear, I was wondering, Lilly Camille King, will you marry me?"

The three-time Olympian answered, "Yes, yes, yes."

The couple kissed and embraced. Wells slipped the ring on King's finger and she commented that it fit perfectly. Then, she excitedly flashed it at the NBC cameras.

Earlier in the week, the 27-year-old King won the 100-meter breaststroke, so she will be representing the US at the Paris Olympic Games in two events. This accomplishment makes King the first US swimmer to compete in both the 100 and 200-meter breaststroke at three consecutive Olympic Games.

On Friday morning, the couple was invited to elaborate on their love story in a segment called "Hoda's Morning Boost" on NBC's TODAY show.

Wells told the TODAY show panel that he had originally intended to propose in England after the Paris Games, but changed his mind because of the Indianapolis venue for the Olympic Team Trials.

"Just seeing Lilly with all of her friends here… in this stadium in our home state, I was like, 'I think this would be a really special moment that she can share with everyone,'" he said. "So I called up a few of my friends that are working here and they got me behind the scenes and kind of set all of this stuff up and it was really awesome."

Both King and Wells swam for Indiana University in nearby Bloomington.

King said that she anticipated a marriage proposal some time after the Paris Games.

"Last night I was not expecting it at all," she said. "I was honestly just so confused why he was on deck. After that, I was like, ‘Why are you wearing your nice clothes, like what’s going on?’ Then I realized, 'Oh I know what’s going on.'"

The couple told the TODAY show panel that they intended to celebrate King's fabulous week by simply going home and hanging out with their pets.

Credits: Screen captures via YouTube / NBC Sports, nbcnews.com.