Zina Garrison defeated U.S. teammate Pam Shriver, 6-3, 6-2, in a quarterfinal Olympic tennis match Tuesday, which guarantees Garrison a second medal and a total of at least seven tennis medals for the United States.
All semifinal performers are assured of a medal because bronze medals will be awarded to losers of both matches.
West Germany's Steffi Graf also advanced, rallying to defeat Larisa Savchenko of the Soviet Union, 6-4, 4-6, 6-3. Graf will play Garrison in one semifinal match, and Gabriela Sabatini of Argentina will meet Bulgaria's Manuela Maleeva in the other.
Shriver had her worst performance of the tournament, hitting repeatedly into the net and failing to reach playable shots. Both players, who are doubles partners as well as roommates in Seoul, said it was difficult to play against each other. Shriver and Garrison have already reached the medal round in doubles.
In the men's doubles quarterfinals, Ken Flach and Robert Seguso of the United States beat Morten Christensen and Michael Tauson of Denmark, 6-4, 7-5, 6-2. Sweden's Stefan Edberg and Anders Jarryd beat Darren Cahill and John Fitzgerald of Australia, 6-3, 6-4, 6-3.
In singles, Tim Mayotte and Brad Gilbert will play in one semifinal match, and Edberg will face Miloslav Mecir of Czechoslovakia in the other.
Water Polo: Terry Schroeder pushed the ball into the net with 3 seconds left Tuesday to give the U.S. a 10-9 victory over Hungary, and advancing the Americans into the semifinal medal round against the Soviet Union.
"All we were thinking is that we had worked too hard to lose," said Schroeder, the U.S. team captain.
The U.S. needed a victory to advance to the medal round, but fell behind with 4 minutes left, 9-8. The Americans rallied, however, and with time running out set up a final shot to Schroeder in the hole. Despite being guarded by two Hungarians, he got the ball past the goalie for the game-winning score.
Entering the game, the U.S. was 3-1-0 and tied with Yugoslavia. However, the U.S. had the edge because it beat the top-ranked Yugoslavs in its opening game, winning in the last second, 7-6.
Looking ahead, U.S. Coach Bill Barnett of Newport Harbor High school said the upcoming game against the Soviet Union Friday will be tough.
"The Soviets are very strong and big," Barnett said. "They are a good team."
The U.S. team finished second behind Yugoslavia at the 1984 Games, and the Soviet Union won the gold ahead of Yugoslavia in 1980.
Volleyball: The U.S. men's volleyball team defeated Tunisia Monday, 15-4, 15-5, 15-4, to win its six-team pool with a 5-0 record. Argentina (3-2) finished second and will advance to the medal round.
In the other bracket, the Soviet Union and Brazil both finished with 4-1 records to qualify for the other two medal-round berths. In Friday's semifinals, the United States will play Brazil and the Soviets will face Argentina. At the 1984 Games, the United States defeated Brazil for the gold medal, 3-1.
Baseball: Ben McDonald pitched the U.S. team to a 7-2 victory over Puerto Rico and into a gold-medal rematch Wednesday against Japan, the defending Olympic champion.
Japan beat the United States, 6-3, for the championship at the Los Angeles Games.
Against Puerto Rico, McDonald, a Louisiana State sophomore, pitched his second complete game. He struck out 7, walked 2 and allowed 9 hits in front of 24,000--the largest audience a U.S. game has drawn in Seoul. Ty Griffin hit a 2-run home run in the 7th inning.
Cycling: Olaf Ludwig of East Germany took the lead with 3 kilometers left and outsprinted West Germany's Brend Groene in the final 300 meters Tuesday to win the gold medal in the men's 197-kilometer road race.
Ludwig's time was 4 hours 32 minutes and 22 seconds. Groene followed by 3 seconds and his West German teammate, Christian Henn, finished third. American Bob Mionske finished a close fourth.
Weightlifting: Pavel Kouznetsov set two Olympic records in the 100-kilogram (220-pound) division Monday to give the Soviet Union its fourth weightlifting gold medal. Andor Szanyi of Hungary, the 1985 world champion, placed second. Romania's Nicu Vlad, a 1984 gold medalist, won the bronze.
Kouznetsov, 27, set an Olympic record in the clean and jerk, 235 kilograms (518 pounds), and in total weight lifted--425 kilograms (937 pounds)--in the heavyweight division.
Wrestling: John Smith, Jim Scherr and Tim Vanni got the U.S. freestyle wrestling team off to a winning start Tuesday with first-round victories.
Smith, the favorite in the 136-pound weight class, defeated Jozsef Orban of Hungary, 11-4. He will wrestle Bulgarian Simeon Chterev in the second round. Scherr beat Canadian Doug Cox, 10-7, at 198 pounds and Vanni shut out Alfredo Marcuno of Spain, 16-0, in the 105-pound division.