Caroline Wozniacki says she's pleased she beat her goal in the New York City Marathon, especially since her training routine included late nights and attending a sporting event on the eve of the run.
"I've done everything you are not supposed to do before a marathon," said the 24-year old Wozniacki. "I had a Halloween party three days ago and came back at like 4:00 in the morning.
"I've been really busy. Last night, I actually didn't have much of a dinner because I went to the (New York) Rangers game. You are supposed to load up on carbs, but I didn't have too much time for that."
The WTA Tour tennis star finished her first marathon on Sunday in just under three hours, 27 minutes, saying she even had enough left in the tank to sprint the final few metres to the finish line.
"It was incredible," said Wozniacki, who set a goal of three hours, 30 minutes.
"I'm so happy to have done this. I'm so proud. Now I have this medal. I can say that I've done the New York City Marathon. I've even done it at a cool time. So I'm really, really happy.
"I've never tried anything this hard. This is like toughest physical test ever. It was so hard. You have to keep going."
The former world number one from Denmark said she would wait a few years before attempting a second marathon. She qualified for the Boston Marathon with her time Sunday.
"Right now I don't think I'm going to do one for a few years, but probably at some point I'm going to do another one."
Asked to compare running a marathon to a five-hour tennis match, Wozniacki said running 26.2 miles (42.2 kilometers) is much more difficult.
"This is completely different," she said. "I had no idea what to expect when I went out there.
"Every time I go on the tennis court, I know exactly what to expect. I know what to do out there. Here I just knew I had to put one foot in front of the other until you see something saying finish."
Wozniacki was met at the finish line by fellow women's tennis star Serena Williams. Williams tweeted about the experience.
"Is it normal to cry when someone finishes a marathon? So proud of you caro @CaroWozniacki #nymarathon," said Williams.
Wozniacki raised over $80,000 for Team for Kids, which provides money for youth running programmes. She said Williams donated "a lot" to the charity but declined to say how much.