BRIEFLY : KRAYZELBURG BREAKS BACKSTROKE RECORD.

Byline: - Daily News Wire Services

When American Jeff Rouse broke the world 100-meter backstroke record in 1992, Lenny Krayzelburg was a 17-year-old Russian migrant trying to start a promising swimming career. On Tuesday, Krayzelburg broke Rouse's world mark at the Pan Pacific championships in Sydney.

``The world record was my goal coming into the meet, but I was surprised it was so fast,'' Krayzelburg said after his 53.60-second performance, breaking the mark of 53.86 that Rouse set at the Barcelona Olympics.

But the 23-year-old Studio City resident, who swam for USC, was overshadowed by Australian Ian Thorpe, who broke his third world record in three days. Thorpe lowered his own mark in the men's 200 freestyle - set on Monday in the semifinals. A scoreboard malfunction cast some confusion on the result, but after a delay Thorpe was given a time of 1:46.0 - breaking his mark of 1:46.34.

BASEBALL: Mark Prior, a freshman All-American pitcher at Vanderbilt last season, has transferred to USC.

Prior, a 6-foot-5, 220 pound right-hander, will be eligible immediately, because baseball players are not required to sit out a season.

``This is very unusual. I think a lot of college baseball people are shaking their heads,'' USC coach Mike Gillespie said. ``We really think he has a chance to be an elite college pitcher. You're getting a guy that's a proven guy with unusual stuff.''

Prior also pitched for the U.S. national team this summer. His record at Vanderbilt was not as impressive as his reputation, but the Commodores were not a highly regarded team. Prior was 4-8 last season with a 4.59 earned run average. He had 71 strikeouts in 82-1/3 innings.

``It's not quite like he dazzled, but he held his own,'' Gillespie said. ``He's not a project. It's a surprise he considered transferring.''

-Scott Wolf

TENNIS: Top-seeded Greg Rusedski, who hadn't played in a tournament since mid-July because of a toe injury, gained a shaky but satisfying 6-7 (3-7), 6-2, 7-5 victory over Kenneth Carlsen in the opening round of the U.S. Pro-Tennis Championships in Brookline, Mass.

Sandrine Testud kept the French on a roll, advancing into the second round of the Pilot Pen tournament with a 7-6 (7-4), 6-3 win over American Tara Snyder. Testud, the eighth-seeded player on the New Haven, Conn., hardcourts, is one of five players from France seeded in next week's U.S. Open, a first for the country.

Thomas Johansson rallied to beat Mariano Zabaleta 5-7, 6-4, 6-3 in the first round of the Hamlet Cup in Commack, N.Y., and end a minislump.