Athens Olympic hero Phelps captured his fourth national title in three days as he triumphed in one of the meeting's marquee match-ups.

His time of 51.51sec was a championships record, while Crocker settled for silver in 51.73.

"The time was a little slow for me," said Crocker, who set the world record of 50.40sec in winning the world title in Montreal last year. "I havent been feeling a lot of speed yet, but this is just the beginning of the championship season.

"I expect to swim faster than that (at Pan Pacs). A world record would always be nice, but sometimes people expect miracles out of us every time we swim. We expect that, too, but youve got to be realistic."

Crocker and Phelps have led the world in this event since Crocker set his first world record in 2003.

Phelps has won five of their eight head-to-head meetings in the event, and all three that Crocker has won have taken a world record to do it.

When we race, we bring out the best in one another," Phelps said. "Its fun to get in the water and race the best, and Ian has proved that he is the best in the 100 fly and its exciting for me to get out and race him."

The womens 100m breaststroke featured the top three US swimmers of all time in that event -- American record-holder Jessica Hardy, former American record holder and 2000 Olympic gold medalist Megan Quann Jendrick and Tara Kirk.

After turning in the top time in this mornings prelims, Jendrick returned to the pool Thursday night to pick up the win with a time of 1:07.54. Hardy and Kirk tied for second in 1:07.65.

"Coming into this meet, everyone was asking me what my goal time was or how fast I thought I could go, but my goal wasnt really a time, it was just to take first or second and make the Pan Pacific team," Jendrick said. "The time was my third-best this season, but like I said, the whole goal was first or second. It feels so good. Its exciting to be back on top."

Hardy jumped out to the lead. She and Kirk were one-two after the turn until Jendrick passed both in the final 30m

"I saw Taras and Jessicas splashes right next to me, so the whole time, I was just like, Keep going," Jendrick said.

Cullen Jones captured the men's 50m freestyle title with a time of 21.94, the fastest in the world this year.

Ben Wildman-Tobriner was second in 22.16 and Jason Lezak third in 22.22.

Veteran Gary Hall and Neil Walker tied for fourth in 22.49.

"A lot of big names in that heat," Jones said. "Gary Hall is definitely one of the guys Ive looked up to since 96, and Lezak, after 2000, I was completely impressed. It was amazing competition."

Katie Hoff broke her own US Open record in the 400m medley with a time of 4:35.82, more than four seconds ahead of the field.

Ariana Kukors was second in 4:40.10 and Kaitlin Sandeno was third in 4:43.06.

The womens 50m free went to Olympian Kara Lynn Joyce in 24.97sec. Five-time Olympic medalist Natalie Coughlin was second in 25.17 and Courtney Cashion third in 25.20.