Katie Ledecky was the fastest swimmer in the pool, and she brought her American teammates along for the ride.

The 19-year-old turned in another overpowering performance to carry the United States to victory in the 4x200-meter freestyle relay, capturing her third gold and fourth medal overall at the Rio Olympics.

The U.S. trailed through the first three legs of the race, as Sweden, China and then Australia swapped the top spot.

Then, it was Ledecky's turn on the anchor leg.

She blew everyone away.

Ledecky turned in a split of 1 minute, 53.74 seconds, which was nearly 2.5 seconds faster than her next-fastest teammate, Allison Schmitt in 1:56.21.

Only one other swimmer in the race, Australia's Emma McKeon, got within a second of Ledecky's four-lap time.

"I was prepared for any circumstance, whether we were ahead of behind," Ledecky said.

The U.S. finished in 7 minutes, 43.03 seconds, with Ledecky a full body length ahead of Tamsin Cook, who touched in 7:44.87 to give Australia the silver. Canada took the bronze in 7:45.39.

And get this: Ledecky's relay time was only one-hundredth of a second slower than her winning time in the 200 free the previous night.

"It's good consistency, I guess," she said nonchalantly.

The teenager from suburban Washington has one more race to go, and it might be the biggest lock of all. She's the world-record holder and defending Olympic champion in the 800 free.

On the fifth night of swimming at the Olympic Aquatic Center, 18-year-old Kyle Chalmers dethroned defending champion Nathan Adrian in the final of the 100 freestyle, the first Australian to be crowned king of speed in 48 years. Kazakhstan claimed its first-ever swimming medal -- a gold one, at that -- when Dmitriy Balandin pulled off a stunning upset in the 200 breaststroke.

Also, Spain's Mireia Belmonte Garcia finally won her first gold medal after two silvers and a bronze, touching first in the 200 butterfly.

Coming off the 20th and 21st gold medals of his career, Michael Phelps wasn't up for any hardware. But he did cruise through the semifinals of the 200 individual medley with the fastest time, besting longtime rival and countryman Ryan Lochte.

Swimming next to Lochte, Phelps put up an effortless-looking time of 1:55.78 to claim the prime middle lane in Thursday night's final.

Lochte will be right next to him again, ranking second in 1:56.28.

Phelps will be seeking his fourth straight 200 IM title at the Olympics. He's also got a chance to pull off that feat in the 100 butterfly.

In the relay, Schmitt captured gold in what was likely the final race of her career. Winner of three golds and five medals overall in London four years ago, she battled depression and didn't qualify for an individual event in Rio. Still, she added two more medals to her trophy case, also getting a silver in the 4x100 relay along with Ledecky.

The other U.S. swimmers were Maya DiRado, who added a gold to go along with silver and bronze in the two individual medleys, and Leah Smith, who picked up her second medal of the games after earning bronze in the 400 free.

Oh, and let's not forget Missy Franklin, the darling of the London Games. She'll also get a gold after swimming in the afternoon preliminaries, though her time wasn't good enough to land her a spot in the evening final.

Franklin's torch has been passed to Ledecky, who joined Phelps and Hungary's Katinka Hosszu as three-time swimming gold medalists in Rio.

In the furious down-and-back sprint that is the 100 free, Chalmers rallied on the return lap to win with a time of 47.58. Pieter Timmers of Belgium claimed the silver in 47.80, while Adrian made it onto the medal podium -- with a bronze this time -- in 47.85.

"It would be great to have gold," said Adrian, who barely advanced out of the preliminaries but nearly pulled off the first back-to-back titles in the 100 since Pieter van den Hoogenband in 2000 and 2004. "But in this day and age, the 100 freestyle is maybe the most fickle event out there. I am so proud to be a medalist for two Olympiads."

For Australia, a country known more for its distance freestylers, Chalmers became the first 100 free champion since Michael Wenden at Mexico City in 1968. The teenager is also the youngest Olympic gold medalist in that event since 17-year-old Jorg Woithe of East Germany at the 1980 Moscow Games.

From lane eight, not normally a spot that produces gold medalists, Balandin put his central Asian country on the swimming map.

Yosuhiro Koseki of Japan went out fast and was more than a second under world-record pace at the final turn. But Balandin was right with him on the outside, and Koseki couldn't keep up the pace.

Balandin touched in 2:07.46, while Josh Prenot of the United States rallied to claim silver in 2:07.53. Russia's Anton Chupkov landed the bronze in 2:07.70, with Koseki fading to fifth.

Balandin pulled himself onto a lane rope and whipped his arms in the air, savoring his historic achievement.

"I'm very proud to win a medal for my country," the 21-year-old said through an interpreter. "It's the best thing I can do for my country."

Belmonte Garcia claimed a pair of silver medals in London, including a runner-up finish in the 200 fly. She made the podium again in Rio by finishing third in the 400 individual medley.

Now, she's on top.

Belmonte Garcia used one last half-stroke to get to the wall ahead of Madeline Groves in 2:04.85. The Australian settled for the silver, just three-hundredths of a second behind. Japan's Natsumi Hoshi claimed the bronze, beating out Cammile Adams of the United States.