RIO DE JANEIRO — Carmelo Anthony had one last thing to teach his young teammates.

On the podium wearing his third Olympic gold medal, Anthony, who led this inexperienced United States team from the moment it first gathered weeks ago in Las Vegas, pointed toward one end of Carioca Arena, to the spot where the American flag was about to rise.

“I just told them, ‘Look at the highest flag,’ ” Anthony said, “and that’s what we did.”

Now there’s nothing left to do for Anthony, whose Olympic career began with a disappointing third-place finish and ends with him being the most decorated player to ever wear a USA jersey. It’s a comeback almost hard to believe.

“I don’t think I can explain how I feel right at this moment,” he said, later adding he will retire as an Olympian.

The only U.S. male player to be chosen for four Olympic teams, Anthony became the first to win three golds as the Americans saved their best for last and crushed Serbia, 96-66, Sunday. Kevin Durant had a game-high 30 points, and Anthony had seven points and seven rebounds in 17 minutes.

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The blowout capped a remarkable 12-year journey around the five interlocking rings for Anthony, only 20 and fresh off his rookie year in the NBA when he played on a 2004 team remembered for failure. The Americans lost three times at the Athens Games, and the sight of them wearing olive wreaths on their heads, bronze medals around their necks and disappointment on their faces, was a low point for the sport’s standard of excellence. USA Basketball was down and deflated.

But along with LeBron James, Dwyane Wade, Kobe Bryant, Chris Paul, Kevin Durant and others, Anthony helped pump pride and power back into the U.S. program, which remains on top of the world.

Anthony grew over his Olympic run spanning games in Europe, Asia and South America. He matured as a person and found his voice, which he has used to address social issues at home. He became more than just a player whose talents seem to perfectly suit the international game. Anthony, so often criticized for not winning an NBA championship, became the model for U.S. players.

He showed commitment, dedication and heart. While James and Paul and other skipped these Olympics, Anthony signed up for another tour of duty to represent his country.

“It’s just his love for the game,” said U.S. forward Paul George, who completed his own amazing story following a horrific leg injury. “It’s his passion for the country and his love for the game, that’s all that it comes down to.”

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During his stay in Brazil, Anthony became the leading scorer in U.S. history. He returned late in the second half of Sunday’s rout just so he could snatch one rebound and move past David Robinson on the career list.

However, Anthony’s most significant mark in Rio may have come when he visited the city’s favelas, blighted areas he compared to Baltimore’s inner city of his youth. It’s another sign of his maturity, which outgoing U.S. coach Mike Krzyzewski saw developing 10 years ago.

After the Americans lost to Greece in 2006 in the FIBA World Championships at Tokyo, Anthony sat at the postgame podium with Coach K and expressed humility and determination.

“He didn’t make any excuses,” Krzyzewski said. “He took responsibility for the loss and gave credit to the Greek team and we’ve built on that. I call it character, and in that moment, sometimes after a loss, you find out a deep character in someone. That’s what happened with Carmelo and in the commitment of LeBron and Kobe and Chris, all these guys have great character and it just built to where we now have a great culture.”

The Americans haven’t lost since, winning 76 games, counting exhibitions.

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A fifth Olympics isn’t in Anthony’s plans, but neither was a dozen years wearing the red, white and blue.

“I’m hanging these things up, USA Basketball-wise,” he said. “It’s been a fun journey for me. It’s been a fun ride. I’ve seen both sides of it. I’ve seen the losing side and I’ve seen what it feels like to win three gold medals. I wouldn’t trade that for anything in the world.”

A few of the victories were more difficult than usual in this tournament, where half of the Americans’ eight games were decided by 10 points or fewer. When the final horn sounded, the U.S. players shared long hugs with each other and then Krzyzewski.

It was a tough ending after an impressive run for Serbia in its first Olympics as an independent nation. The heart of an international power in the former Yugoslavia, the Serbs hadn’t qualified for the Olympics since gaining their independence in 2006. They dropped three games in the group stage but had the look of a team that could challenge the Americans after nearly knocking them off earlier in the tournament and overwhelming Australia in the semifinals.

They were down just 16-15 before Durant made a three-pointer for the final points of the first quarter, and before they knew it he had turned the game into a blowout.

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“They are superstars. If you let them play like they want, they will kill you,” guard Stefan Markovic said. “Each of their 12 guys can do that.”

A challenging year for the Americans started long before they boarded the cruise ship they stayed on while in Rio. For the first time since 2004, many top American players opted to skip the Olympics, forcing them to bring some here who wouldn’t have been considered otherwise.

The 10 Olympic newcomers seemed to be jelling slowly and the U.S. had a pair of three-point victories and came in winning by just 21.4 points per game, more than 10 per game fewer than four years ago and about half the 43.8 the Dream Team won by in 1992.

“This team kept getting better, and even those three games in pool play, we had not played that type of game against that type of level of opponent,” Krzyzewski said. “We said it was a learning experience and our guys did learn and we put it to good practice.”

Krzyzewski, an assistant on the Dream Team, has long insisted that international basketball has gotten too strong for anyone to win that easily again.

Yet on Sunday, the Americans did.