RIO DE JANEIRO (AP) Katie Ledecky has never felt such pain. She actually felt like she might throw up in the pool.
That wasn't enough to slow the gritty teenager.
Ledecky took the most challenging step toward a feat that's only been done one other time, holding off Sweden's Sarah Sjostrom to win the 200-meter freestyle Tuesday and give the American star her second gold of the Olympics.
Debbie Meyer is the only female swimmer to capture the three longest freestyle events at a single Olympics, winning the 200, 400 and 800 at the 1968 Mexico City Games. Now that the 200 is out of the way, Ledecky is essentially a lock to match Meyer.
The 19-year-old from suburban Washington crushed the world record in the 400 and will be an overwhelming favorite in the 800, where she's the world-record holder and far faster than anyone else in the world.
The 200 was the only one really in doubt.
''That was a really tough race and it hurt really badly,'' Ledecky said. ''I'm pretty sure it's the closest I've come to throwing up in the middle of a race. I'm just so glad I got my hand on the wall first and it was all worth it.''
Fifth at the first flip turn, a bit faster than she usually goes out, Ledecky powered to the front on the third lap and feistily fended off a hard-charging Sjostrom coming to the wall.
Ledecky touched in 1 minute, 53.73 seconds. The silver went to Sjostrom in 1:54.08, while early leader Emma McKeon faded to the bronze in 1:54.92. World-record holder Federica Pelligrini of Italy was fourth.
This may be the shortest race on Ledecky's program but it's definitely her toughest, requiring both speed and endurance against a far more competitive field.
''The 200 is a much more stressful race than the 400 and 800, and it always just feels good when it's over,'' she said. ''I took it out pretty fast and kind of forced everybody to try to do that. Once I was ahead I knew I wasn't going to let it out of my hands. I knew I wasn't going to be able to see most of the field on the last 50, so I just had to dig deep.''
Ledecky also claimed silver in the 4x100 free relay and has two more races to go, setting herself up for a medal haul that would fully live up to the enormous expectations she faced coming into the Olympics.
In addition to the 800, she'll likely be the anchor on the 4x200 freestyle relay, another event where the Americans are a big favorite.
Follow Paul Newberry on Twitter at www.twitter.com/pnewberry1963 . His work can be found at http://bigstory.ap.org/content/paul-newberry .