World records tumble at U.S. trials

OMAHA, Nebraska (Reuters) - Natalie Coughlin and Hayley McGregory blitzed to back-to-back world records and Katie Hoff secured her second Olympic berth at the U.S. swimming trials on Monday.

Just two days into the eight-day competition, four world records have fallen as American swimmers engage in a cut-throat battle for places in the Beijing Olympic team.

With only the top two finishers in each event qualifying, the competition has been fierce.

Even though McGregory and Coughlin posted world records in the 100 meters backstroke preliminaries, that was only good enough to take them as far as Tuesday's final.

Hoff, however, coming off a world record in the 400m medley on Sunday, qualified for her second Olympic event by touching first in the 400m freestyle with the third best time this year of four minutes, 2.32 seconds.

Day two got off to an electric start when McGregory powered home in a time of 59.15 during the morning heats to steal Coughlin's world record.

But McGregory's reign lasted only as long as it took Coughlin to complete her heat, the 25-year-old storming to the wall in 59.03 to retake her record.

Neither swimmer was able to better that time in the evening semi-finals but both easily won their heats to set up a mouth-watering showdown in the final.

"It just felt different, my body was a little tight," McGregory told reporters. "Natalie and I have different strengths and I don't get to swim against her very often."

Michael Phelps was left to celebrate his 23rd birthday quietly by qualifying for the 200 meters freestyle final.

EASY WINS

A day after demolishing his own world record in the 400 medley, Phelps was back in the pool and cruising to easy wins in his preliminary and semi-final heats.

Ryan Lochte, who chased Phelps to his 400 individual medley record, set up another showdown with the six-times Olympic gold medalist in Tuesday's 200m final after clocking the year's best time of 1:45.61 to win his semi-final.

"I'm happy with it," said Phelps, who is targeting Mark Spitz's record of seven gold medals at a single Summer Olympics. "I'm getting a good feel for my stroke."

World record holder Brendan Hansen set the stage for an Olympic showdown with arch-rival Kosuke Kitajima of Japan by touching first in the 100m breaststroke in 59.93.

"I didn't break my world record but having that Olympic berth solidified feels very good," Hansen said. "I think for everyone of us this is the toughest part of the summer, trying to make the Olympic team."

In the 100m butterfly final, Christine Magnuson came home first in 58.11 ahead of Elaine Breeden and both women qualified for their first Olympics.

(Editing by Ed Osmond)

(For more Olympic stories visit our multimedia website "Road to Beijing" here; and see our blog at blogs.reuters.com/china)