Olympic gold medalist

Antonio Pettigrew

admitted publicly for the first time yesterday that he used performance-enhancing substances during a long, successful sprinting career in which he passed all drug tests.

The admission came during the last day of testimony for the government in the San Francisco trial of his former coach,

Trevor Graham

, who is accused of lying to federal authorities investigating doping in sports. Graham has pleaded not guilty.

It also was revealed that Olympic sprint champion

Justin Gatlin

worked undercover for authorities investigating doping in sports, according to the testimony of IRS agent

Erwin Rogers

.

Pettigrew lied to federal investigators and denied doping in February 2005. But he finally confessed behind doors to cheating when confronted with documents in October 2006 strongly suggesting drug buys.

Pettigrew won a gold medal as part of the U.S. 4x400-meter relay team at the 2000 Sydney Olympics. He retired from track in 2002 and is now an assistant coach at the University of North Carolina.

The Senate Foreign Relations Committee held a hearing on the International Convention Against Doping in Sport, which has been ratified by more than 80 countries. Ratification is considered a prerequisite for hosting an Olympics. The United States is the only country among the seven bidding for the 2016 Games that hasn't put the treaty into law.

Tennis

The United States lost, 2-0, to Sweden, in the World Team Cup in Duesseldorf, Germany.

James Blake

lost, 5-7, 6-3, 6-0, to undefeated

Robin Soderling

and

Thomas Johansson

stopped

Bobby Reynolds

, 6-3, 2-6, 6-3.

Sweden advanced to tomorrow's final.

Elsewhere:

Australian Open finalist

Jo-Wilfried Tsonga

defeated

Santiago Ventura

, 6-3, 6-3, to reach the semifinals of the Grand Prix Hassan II in Casablanca, Morocco. . . .

Nikolay Davydenko

,

Juan Monaco

,

Ivan Ljubicic

and

Igor Kunitsyn

reached the semifinals of the Hypo Group International in Poertschach, Austria.

Colleges

Villanova righthander

Bill Hoffman

pitched a complete-game, five-hit shutout as the Wildcats advanced to the semifinal round of the Big East Conference baseball tournament with a 10-0 win over Seton Hall at Bright House Field in Clearwater, Fla. Hoffman (6-1) struck out nine and allowed just one runner to reach third base.

Villanova (30-27) will face Louisville at 10 a.m. today in the semifinals.

The Big Five's co-MVPs were invited to the NBA's predraft camp, to be held next week in Orlando, Fla. Temple's

Mark Tyndale,

a 6-foot-5 guard from Simon Gratz High, and St. Joseph's

Pat Calathes

, a 6-10 forward from Casselberry, Fla., earned invitations.

Former Southern California basketball star

O.J. Mayo

has been dropped by his agents ahead of the June 26 NBA draft because of the "overwhelming intensity" of allegations that Mayo illegally received cash and gifts. Bill Duffy Associates of Walnut Creek, Calif., issued a statement saying their association was over. Mayo has denied the charges.

Elsewhere:

Marquette guard

Jerel McNeal

and Alabama forward

Alonzo Gee

withdrew from the NBA draft to return for their senior seasons. . . . South Carolina forward

Chad Gray

was dismissed from the men's basketball team by new coach

Darrin Horn

for repeated violations of team rules. . . . Indiana coach

Tom Crean

dismissed forward

Brandon McGee

from the team because of academic and team guideline violations. . . . Nevada women's basketball coach

Kim Gervasoni

announced her resignation. . . .

Dwain Williams

will transfer from Providence to Long Beach State, Friars coach

Dan Monson

said. . . . Temple lost to Duquesne, 10-7, at Campbell's Field and was eliminated from the Atlantic Ten Conference baseball tournament.

Noteworthy

Kyle Busch

turned in a lap of 185.433 m.p.h. Toyota to edge

Kasey Kahne

(185.300) and win the pole for Sunday's Coca Cola 600 at Lowe's Motor Speedway in Concord, N.C.

Elsewhere:

Glasgow Celtic won, 1-0, at Dundee United to claim the Scottish league title for the third consecutive year and 42d time overall. . . . World-record holder

Paula Radcliffe

of England might not compete in the marathon at the Beijing Olympics because of a stress fracture in her left thigh bone. . . .

Tony Granato

was promoted to head coach of the NHL's Colorado Avalanche, replacing

Joel Quenneville

.