Andre Agassi clinched the No. 1 spot in the year-end tennis rankings for the first time, ending the six-year streak of Pete Sampras, who hurt his back and withdrew from the Paris Open yesterday.

Agassi, who won the French and U.S. open titles and lost the Wimbledon final to Sampras, was ensured the top ranking when Lleyton Hewitt upset No. 2 Yevgeny Kafelnikov, 6-4, 2-6, 6-4, in the second round of the Paris Open.

Sampras, ranked third, was hurt late Tuesday in a 4-6, 6-3, 7-6 (7-4) win against Francisco Clavet. That was Sampras's first match since Aug. 20, when he injured his right hip in a match in Indianapolis.

Nine days later, Sampras herniated a disk while practicing for the U.S. Open and had not played until Paris.

Agassi is the 10th player to finish No. 1 in the 27-year history of the ATP Tour rankings. It comes two years after his ranking had plummeted to 141st.

Sampras would not speculate on how long he'll be sidelined; tournament trainer Per Bastholt said he will be out 10 to 15 days.

"My left side got tighter and tighter," Sampras said yesterday. "I felt it get worse and there was a complete spasm."

Greg Rusedski, who beat Sampras in last year's final, also withdrew because of injury. In other upsets, Marc Rosset beat 12th-seeded Alex Corretja, 7-5, 6-3; Mark Philippoussis defeated eighth-seeded Richard Krajicek, 7-5, 6-3; and Jim Courier downed 14th-seeded Carlos Moya, 6-2, 6-1.

Golf

Parnevik Is Ailing

Jesper Parnevik, Europe's top player in the Ryder Cup, withdrew from the World Golf Championship event in Sotogrande, Spain, because of heart problems and probably won't play the rest of the year.

His mother, Gertis, said her 34-year-old son was experiencing pain and had an irregular heartbeat. She said his sleep had been affected and said he keeps a machine to check his heart rate.

Parnevik, known for wearing the bill of his cap flipped up, was 3-1-1 in the Ryder Cup. His condition most likely will keep him from the Million Dollar Challenge in South Africa next month.

His medical problems could help him restore his eligibility on the European tour.

The tour said Tuesday that Parnevik lost his full membership because he failed to play the required 11 tournaments--Valderrama would have given him enough events. Without membership, he might not be eligible for the Ryder Cup in 2001.

But tour spokesman Gordon Simpson said Parnevik could give medical reasons for his absence and a committee could reinstate him. . . .

Golfer Tiger Woods won his second PGA of America player of the year award after winning seven tour events, including last week's PGA Tour Championship.

Football

Cardinals Hurting

The Arizona Cardinals' defensive line, once considered the team's biggest strength, has received two serious setbacks: tackle Mark Smith will not play again this season and end Andre Wadsworth will be out several weeks after having arthroscopic knee surgery yesterday.

Smith's season ended when it became apparent that he would not be able to come back from arthroscopic surgery on his right knee. The Cardinals had expected Smith to return four to six weeks after the operation.

Smith held out in a contract dispute before accepting the Cardinals' offer after missing two games. He played in only two games before going out with the knee injury.

Wadsworth had arthroscopic surgery on his right knee, which has been hurt since the second preseason game. Under normal circumstances, a player who undergoes that type of procedure is out four to six weeks, although Wadsworth has insisted he expects to be back sooner. Wadsworth also has had a wrist injury and turf toe. . . .

Dallas Cowboys quarterback Troy Aikman was cleared to play after an MRI exam showed he suffered no damage from a blow to the head.

Cowboys officials said the results of Tuesday's precautionary MRI show Aikman did not have a concussion and that he will be able to play in the Cowboys' Monday night game in Minnesota.

Basketball

WNBA Picks Phoenix

The summer heat hasn't turned off Phoenix Mercury fans, and the WNBA expects a good crowd for its second all-star game.

The inaugural game was held in New York's Madison Square Garden last summer and attracted a sellout crowd of 18,649.

This contest will be played July 17 in the America West Arena, site of the 1995 NBA All-Star Game.

Locally

Chastain to Be Honored

Women's World Cup star Brandi Chastain will be honored by America Scores, a Washington-based urban youth soccer and creative writing program, at its fund-raiser Nov. 12 at Capitol City Brewery in the District.