RIO DE JANEIRO » Katie Ledecky came into the Rio Olympics facing enormous expectations.

Some athletes might’ve buckled under the pressure.

She seemed to thrive on it.

The 19-year-old from suburban Washington capped off one of the greatest performances in Olympic history with her fourth gold medal and second world record, shattering her own mark in the 800-meter freestyle Friday night.

“I just wanted to lay it all out there,” Ledecky said.

She certainly did that.

And more.

Ledecky and Debbie Meyers are now the only female swimmers to sweep the three longest freestyle races. Meyers took the 200, 400 and 800 at Mexico City in 1968.

She also followed fellow swimmers Amy Van Dyken and Missy Franklin as the only American women to win as many as four golds in a single Olympics. Along with her individual golds, Ledecky also topped the podium with the 4×200 relay.

“I hit all my goals right on the nose this week,” Ledecky said. “I’m just proud to be part of that history.”

Four years ago, she seemingly came out nowhere to capture gold as a 15-year-old at the London Games. Then, after her coach moved to the West Coast, Ledecky hooked up with Bruce Gemmell and never missed a beat.

She called it “a testament to the vision that Bruce and I had three years ago when we set these goals, and we weren’t going to stop until we met them.”

As was the case in the 400 free, where she also broke her own world record, Ledecky was merely racing the clock as she powered away from the field to touch in 8 minutes, 4.79 seconds, eclipsing the mark of 8:06.68 that she set at a grand prix meet in Texas back in January.

“The goal was 8:05 or better,” she said.

Naturally, she was better.

Then, Ledecky played the waiting game, hanging on the rope for a while to let the rest of the field finish.

Jazz Karlin finally touched in 8:16.17 to claim the silver, just ahead of Hungary’s Boglarka Kapas grabbing the bronze in 8:16.37.

Some 23 seconds after Ledecky touched the wall, the last of the eight finalists chugged to the end of the grueling race.

Ledecky was barely breathing hard.

On the medal stand, though, the emotions swept over her.

She broke down in tears, relishing her accomplishments and surely thinking about all the work she put in to make it there.

“The Olympics are the pinnacle of our sport and I have to wait another four years to have that moment and I just wanted to enjoy it,” Ledecky said. “The memories mean more than the medals to me.”