RIO DE JANEIRO — When Stanford swimmer Simone Manuel touched the wall to clinch a gold medal Saturday night, it was a moment 120 years in the making.

The U.S. women”s 4×100-meter medley relay team of Kathleen Baker, Lilly King, Dana Vollmer and Manuel — winners at the Rio Games on Saturday night — is being recognized by the U.S. Olympic Committee as delivering the nation”s 1,000th gold medal in Summer Olympics history.

“A thousandth gold for team USA,” said Manuel, who swam the anchor leg for her second gold of the games and second medal of the night. “It”s a nice number.”

The historic victory came with a time of 3:53.13.

“It”s really special,” Manuel said. “Sharing that with three other women is just icing on the cake.”

Earlier in the night, Manuel took silver in the 50 freestyle. She already became the first African-American woman to win an Olympic swimming title with her win in the 100 free. Pernille Blume of Denmark held off Manuel to capture gold.

Meanwhile, the Americans finished off the final night at the Olympic Aquatics Stadium by equaling their biggest medal haul in the last three decades.

Michael Phelps, Katie Ledecky & Co. made sure the U.S. stayed firmly atop the swimming world.

“We all know we”re part of a really special team,” Ledecky, the incoming Stanford student, said, five medals hanging from her neck after one of the greatest performances in Olympic history. “We have such great depth in the U.S. in swimming, and it”s something we take great pride in. This is kind of our stage to show the world that.”

The Americans piled up 16 golds and 33 medals overall, matching their total from the 2000 Sydney Games.

Phelps, of course, led the way. In what he again insists will be his final Olympics, the 31-year-old piled up five golds and a silver, bouncing back from a stunning upset by Singapore”s Joseph Schooling in the 100-meter butterfly to help power the U.S. to victory in the final event at the pool, the 4×100 medley relay.

Phelps put the United States ahead to stay on the butterfly leg of the relay and Cal”s Nathan Adrian finished it off, giving the most decorated athlete in Olympic history his 23rd career gold medal. As Adrian touched the wall to finish off the victory, Phelps gathered the other relay swimmers, Cal”s Ryan Murphy and Cody Miller, in his arms. One night after his only setback in Rio, an upset loss to Schooling, Phelps was back on top.

But no one was more dominant than the 19-year-old Ledecky, whose four golds included two world record-shattering performances. She joined Amy Van Dyken and Missy Franklin as the only American women to capture as many as four golds in a single games, matched Debbie Meyer as the only females to sweep the 200, 400 and 800 free, and also won silver anchoring the 4×100 free relay.

“What she”s doing in the sport is ridiculous,” Phelps said.

There”s something to be said for the camaraderie displayed by the American team.

During their final training session in Atlanta, a host of swimmers — Phelps and Ryan Lochte among them — took to the streets to record a James Corden-style carpool karaoke video. Even Ledecky took a turn behind the wheel, even though she still has just a learner”s permit.

“I was only at a gas station,” she quipped, “so I didn”t think I was going to hurt anyone.”

When the swimmers got to Brazil, they received a history lesson from one of the coaches, Greg Meehan. At a meeting with the female athletes on the eve of the games, he told them about the Homestead Act, the 1862 law that encouraged America”s westward migration by providing free land to settlers.

We”ll let Ledecky take it from there.

“We each had American flags and they printed out each of the events, and the people that were competing in each of those events came forward, had a little moment together, took the flag and stuck it through the paper and into the grass in the Olympic village,” she said. “We were just kind of staking our claim in Rio, and I think we kind of did that in the pool as well.”

In addition to Phelps and Ledecky, the biggest U.S. stars were Stanford”s Maya DiRado, who turned in the ultimate one-and-done with two golds and four medals overall; Murphy, who extended U.S. men”s dominance of the backstroke; Manuel; King, who backed up her brash diatribe against doping; and Anthony Ervin, the oldest member of the team at 35 and a gold medalist again in the 50 free — 16 years after he first won the event in Sydney.

Even with a hugely disappointing performance by Franklin, who didn”t even make it to the final of her two individual events, the Americans still blew everyone away. Connor Jaeger gave the U.S. another silver in the 1,500 free.

There are several factors that go into the success of the U.S. program, starting with some simple numbers. The Americans have far more swimmers and resources to draw from than most nations, so it”s only natural they would dominate.

Beyond that, Ledecky pointed to a U.S. trials format that sets up the team to perform well at the Olympics. Over eight nights in Omaha, just a month before the games and following the same schedule of events, swimmers earned their way onto the team before sellout crowds of more than 14,000 at every session.

That was bigger than the crowds in Rio, where there were plenty of empty seats each night.

“It”s an overly easy environment for us to swim fast in because we”ve been through our Olympic trials, which is way more pressure-filled than the Olympics,” Ledecky said. “Obviously the crowd here hasn”t been that intimidating to us.”

Nothing was too intimidating to the Americans.

Manuel, the American co-gold medalist in the 100 free, settled for silver in 24.09. Aliaksandra Herasimenia of Belarus earned the bronze in 24.11.

It was another huge disappointment for sisters Cate and Bronte Campbell of Australia. They were shut out of an individual medal again, with Cate finishing fifth and Bronte seventh.

mark purdy:

Phelps doesn”t disappoint in likely final Olympic race. A1