Toby Stanley and 16-year-old Gracia Leydon-Mahoney led their divisions Thursday after the semifinal rounds in the U.S. national diving championships.

Stanley, from Conway, Ark., finished with 481.35 points in the men's 10-meter platform to top the 12 qualifiers for Sunday's finals. Stanley, who also led after Thursday's preliminaries, had four dives of 80 points or better. That included the semifinal's best single dive, a 94.35 on a forward 4 1/2 somersault tuck.

"I didn't do too hot at the Olympic trials (finishing ninth), and that really bothered me," Stanley said. "I had been training a lot, but I've changed my approach since then. I've literally doubled my training - eight hours a day, 48 hours a week. It's a full-time job, but it's paying off."

Steele Johnson of Carmel, Ind., was second at 440.10, and Logan Shinholser of Burtonsville, Md., was third at 429.35.

Leydon-Mahoney, from Durham, N.C., had 312.10 points to top the women's 3-meter springboard semifinals, with the top 12 advancing to Sunday's finals. Samantha Pickens of Tucson, Ariz., was second at 304.30 points. Cheyenne Cousineau of Temperance, Mich., finished third at 288.80 points.

Leydon-Mahoney, who finished third in the event at the U.S. junior nationals last week, also had the semifinal round's best dive, scoring 71.40 points on a back 2 1/2 somersault tuck. She closed out with two more dives scoring 60 or more points.

"My first two dives weren't bad, but I was trying to put a little something extra on it," said Leydon-Mahoney, who was third after Thursday morning's preliminary round. "I was still happy with them. But the third dive, that's one of my best dives. All the other divers are good divers, so it's going to come down to whoever shows up and competes well that day."

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