Even a nervous Katie Ledecky can't be caught

— -- OMAHA, Neb. -- On her path to becoming the most dominant swimmer in the world, Katie Ledecky used her first event of the 2016 U.S. Olympic trials Monday to remind the world that she is, in fact, human -- and still a teenaged one at that. It had nothing to do with Ledecky's performance in the water. The 19-year-old blitzed the field in the 400 freestyle and brought a charge to the arena by swimming ahead of world-record pace for three-quarters of the race.

The reminder that Ledecky isn't in fact a swimming robot came from her admission that she spent the 24 hours prior to competition fighting pre-meet jitters and struggled to get much rest. On Sunday night, she crawled into bed at 9:30 p.m. but didn't fall asleep until 11:45. Then, after her 400 free preliminary Monday afternoon, she tossed and turned in her hotel room bed before eventually giving up and watching television.

"I just put the TV on and laid there," she confessed. "CNN -- that's my go-to."

The revelation was just a small glimpse into the world of the young woman who is about to embark on the biggest summer of her life. Monday night was simply the opening chapter of the Summer of Katie Ledecky. She wasn't fully rested, but even so, halfway through the four-minute race, she was more than two seconds ahead of her 2014 world-record pace. At the beckoning of the stadium announcer, the 14,000 fans jammed into CenturyLink Center stood on their feet and jumped up and down, hoping to witness history. Watching on a massive TV screen next to the warm-down pool, Ledecky's coach, Bruce Gemmell, had a different thought.

"Maybe that's too fast, maybe that's too hard," Gemmell said. "I didn't think it was disastrous. Let's not get carried away. I was thinking ... she might regret it when she gets on the back 200. But you can never be sure of that. In London, everyone said she's going out too fast, but it certainly didn't prove that way."

Four years ago in London, as a 15-year-old, Ledecky won her first Olympic gold in the 800 free but fell short of a world record. On Monday, she was .96 seconds ahead of world-record pace at 300 meters. When she touched the wall for her last 50, that advantage shrunk to .39 seconds. The crowd roared even louder, trying to push her home. But with a :30.90 final split, Ledecky's winning time of 3:58.98 missed the mark by .61 seconds.

Afterward, she said she was more excited by the performance of Leah Smith, whose second-place time of 4:00.65 was nearly three seconds faster than anyone else in the world and made Smith the fourth-fastest performer of all-time.

"I was more pumped about that race than mine," Ledecky said. "I mean, that's fast. We're going to really represent the U.S. well."

Added Gemmell: "If you know Katie, that's pretty indicative of her right there."

Smith said after her race that it had been a goal since she was a little girl to break four minutes. To finally be so close to that mark was "pretty cool." At a grand prix meet in Minnesota in November, Smith said she could barely see Ledecky's feet during the race. That changed Monday, despite Smith's planning for the opposite.

"My goal wasn't to stay with her," Smith said. "That would be a stupid plan."

That, too, is a glimpse into Ledecky's dominance in the pool. Trying to keep up with her can prove calamitous to her competition. In most events, the question is not whether Ledecky is going to win but by how much. Her races are often a relative bore, with Ledecky pushing herself to a sizable lead and never looking back. Unlike 2012, when fans were transfixed by the rivalry between Michael Phelps and Ryan Lochte heading into London, at this point, Ledecky has no peers, which makes Smith's finish 1.67 seconds behind her a moral victory.

In the 400 free, Ledecky owns eight of the top 10 times ever. Italy's Federica Pellegrini occupies the other two spots, and both of those swims came in 2009, before Ledecky was even a teenager. In the 800 free, Ledecky is even more dominant, as she owns the eight fastest times in history with a nearly eight-second advantage over any other swimmer.

Last summer at World Championships in Russia, she became the first woman to win gold in the 200- 400- 800- and 1500-meter freestyle events, now known as the Ledecky slam. But in the U.S., it is of course the Olympics that matter most, which is why this will be the summer that Ledecky becomes a household name from coast to coast.

On Tuesday, she will compete in the prelims of the 200-meter freestyle, another event in which she is the top seed. Some believe that, long-term, she has the potential to be the world champion and record holder in every freestyle event from the 100 to 1,500 (which isn't swum in the Olympics), a monumental accomplishment in a sport dominated with specialization that separates the sprinters from the distance swimmers.

Ledecky's talent leads to preposterous suggestions, such as whether she can drop her world record time by another six seconds. It isn't all that laughable. When asked after Monday night's victory if fans could see a negative split, in which a swimmer performs the second-half of a race faster than the first, Gemmell replied, "Not if she goes out in a 1:56.2, you're not." When a reporter followed up wondering whether Ledecky had the potential to swim the 400 free in 3:52, Gemmell put a cap on his young star's abilities.

"No," he said. "There. I'll say it."

It won't happen in what is expected to be a magical summer. But given what we've seen from Ledecky so far and what is expected on the road ahead, perhaps nothing is off the table.