Claressa Shields after gold-medal win: 'I'm one of the great boxers to ever live'

After American Claressa Shields, then 17, won the women's middleweight Olympic gold medal at the 2012 London Games, her goal was to repeat. She said she wanted to prove her championship was no fluke in the first year that women's boxing was contested in the Olympics.

Four years later, mission accomplished for the best female amateur boxer in the world.

In dominant fashion, Shields won all four rounds on all three judges' scorecards to outpoint Nouchka Fontijn of the Netherlands and defend her 165-pound gold medal Sunday afternoon at the Rio de Janeiro Olympics.

"I wanted to let everyone know that I'm not just a great female boxer but I'm one of the greatest boxers to ever live," an overjoyed Shields said after the bout. "I'm the first American to be a two-time Olympic gold medalist. Oh, my god!"

Shields, 21, of Flint, Michigan, made history by becoming the first American boxer to win back-to-back Olympic gold medals as she whipped the 28-year-old Fontijn in a rematch of Shields' victory at the 2016 world championships.

The heavy pre-tournament favorite to repeat, Shields became just the second American to win two Olympic boxing medals. At the 1904 St. Louis Games, Oliver Kirk won both the bantamweight and featherweight gold medals, but no American ever returned to the Olympics to win a second consecutive gold.

Shields' improved her Olympic record to 6-0 and is a staggering 77-1 overall. She has not lost since 2012 and has won the past two world championships.

Shields was dominant from the outset against the taller Fontijn, who was bidding to win the first Olympic boxing gold medal for the Netherlands since 1928.

Fontijn was moving, staying away and attempting to box on the outside, but Shields sized her up and moved forward, throwing overhand rights and left hooks to easily win the opening round.

It was more of the same for the next three rounds as Shields landed to the body and head with an assortment of hard combinations.

Late in the fourth round, Shields connected with a sharp right hand that snapped Fontijn's head back.

Shields said her plan for the bout was to "just to be smart. Use my jab and land the right hand when I could. And not get touched by those long arms that she had, and I did it."

After the decision was announced, Shields dropped to one knee as the referee raised her arm in victory and then got up and did a cartwheel before posing for photos with a big smile on her face. She exited the ring and, with an American flag draped over her shoulders, ran laps around it to celebrate her historic achievement.

When Shields was a little girl, she was not even aware that women's boxing existed until somebody told her about Laila Ali, who is widely considered the best women's fighter in history. Laila Ali, daughter of the late Muhammad Ali, retired undefeated at 24-0 in 2007 and is the last women's boxer to make an impact in the pro ranks.

Shields could be next. There are promoters and television networks interested in her should she elect to go pro. But in the immediate aftermath of her second gold medal, it was too soon to say for sure what she planned to do.

"I don't know, I don't know, I don't know," Shields, still wrapped in her American flag, said when asked about what she would do next.

One thing she surely does know, however, is that she is going to celebrate her golden day.