Two members of the U.S. Olympic Greco-Roman wrestling team have won their pool competition and moved into the championship bracket at the Poddoubny Tournament in Podolsk, Russia, August 4-5. The athletes who still have an opportunity for a medal include Garrett Lowney (Appleton, Wis./Minnesota Storm) at 213.75 pounds and Rulon Gardner (Afton, Wyo./Sunkist Kids)  at 286 pounds. The tournament will be completed on Sunday, August 6.    The Poddoubny Tournament is considered the most challenging open international Greco-Roman tournament in the world each year. The U.S. team is using the competition as part of its preparation for the 2000 Olympic Games in Sydney, Australia.    Lowney won his pool competition with two victories. He scored a 1-0 overtime referee's decision over Konstantin Batyaev of Russia in his first match, and defeated Alexander Arhangelski of Russia, 3-1, in overtime at 7:48 in the second match. Lowney moves into the championship bracket, which features five competitors. Lowney was a 1999 Junior World Champion.    Gardner scored a pair of convincing victories, beating Sergei Bosketov of Russia, 8-0, then scoring an 11-0 technical fall over Alexander Kuznitzov of Russia, in 2:59.  Gardner  moves into the championship bracket, which features five competitors. Gardner was fifth in the 1997 World Championships.     The other six U.S. Olympic team members in the competition were unable to win their pool competition, and did not advance into the championship bracket. These U.S. wrestlers will not compete again, and are not eligible for medal contention. All six wrestlers claimed one victory and suffered one defeat in their pool competition.    Two of the U.S. Olympic wrestlers were competing up one weight class:  Steven Mays (Pensacola, Fla./U.S. Navy) and Heath Sims (Huntington Beach, Calif./Dave Schultz WC). Mays, who will compete at 119 pounds at the Olympics, wrestled at 127.75 pounds in this event. Sims, who will wrestle at 152 pounds at the Olympics, wrestled at 167.5 pounds in Russia.    The other four U.S. Olympic wrestlers who lost in their pool competitions were  Jim Gruenwald (Colorado Springs, Colo./Sunkist Kids) at 127.75 pounds,  Kevin Bracken (Chicago, Ill./New York AC) at 138.75 pounds, Keith Sieracki (Colorado Springs, Colo./U.S. Army) at 167.5 pounds and  Quincey Clark (New Brighton, Minn./Minnesota Storm) at 187.25 pounds.    One other U.S. wrestler entered the tournament, U.S. Olympic Trials runner-up Glenn Nieradka (Colorado Springs, Colo./U.S. Army) at 138.75 pounds. Nieradka had a 2-1 record in his pool, and did not advance.    The team is led by U.S. Olympic Greco-Roman head coach Dan Chandler of Minneapolis, Minn. and assistant coach Rob Hermann of Pensacola, Fla. along with National Greco-Roman coach Steve Fraser of Colorado Springs, Colo.     Only two U.S. wrestlers have ever won a gold medal at the Poddoubny Tournament, Shawn Sheldon, who won the 114.5-pound title in 1989  and Dan Russell, the 163-pound champion in 1995.     The U.S. Greco-Roman team will hold one segment of training camp in the United States when they return from Russia. The camp will be held at the U.S. Olympic Training Center in Colorado Springs, Colo. Aug. 14-26. Other members of the National Greco-Roman Team and other talented training partners will attend Training Camp along with the Olympic team members. Another segment of training camp will be held in Canberra, Australia before the Games begin in September.     PODDOUBNY TOURNAMENT at Podolsk, Russia, August 4-6    U.S. results in the pool competitions    58 kg/127.75 lbs. - Steven Mays, Pensacola, Fla. (U.S. Navy) - dec. Shota Simonia (Russia), 4-3; lost pin to Alexander Borisov (Russia), 2:48    58 kg/127.75 lbs. - Jim Gruenwald, Colorado Springs, Colo. (Sunkist Kids) - won by tech. fall over Islam Umazakov (Kyrgyzstan), 10-0, 4:01; lost dec. to Viacheslav Nemtchenko (Russia), 3-2    63 kg/138.75 lbs - Kevin Bracken, Chicago, Ill. (New York AC) - lost dec. to Nikolai Monov (Russia), 4-3; won by tech. fall over Valentin Molutin (Kyrgyzstan), 10-0, 5:47     63 kg/138.75 - Glenn Nieradka, Colorado Springs, Colo. (U.S. Army) - lost dec. to Vateres Samorgoshev (Russia), 5-0; dec. Artur Lizev (Russia), 5-0; dec. Alexei Mazur (Ukraine), 5-0    76 kg/167.5 lbs. - Heath Sims, Huntington Beach, Calif. (Dave Schultz WC) - lost by ref. dec. to Jahongier Turdeev (Uzbekistan), 2-1, ot, 9:00; dec. Vadim Alajev (Russia), 3-0    76 kg/167.5 lbs - Keith Sieracki, Colorado Springs, Colo. (U.S. Army) - lost dec. to Daniel Halimov (Russia), 5-4; dec. Nurlan Jongitiev (Kazakhstan), 5-0    85 kg/187.25 lbs - Quincey Clark, New Brighton, Minn. (Minnesota Storm) - lost dec. to Mohammed Abdel Fatah, 6-1; dec. Alexander Soldotov (Russia), 4-1    97 kg/213.75 lbs. - Garrett Lowney, Appleton, Wis. (Minnesota Storm) - won by ref. dec. over Konstantin Batyaev (Russia), 1-0, ot, 9:00; dec. Alexander Arhangelski (Russia), 3-1, ot, 7:48    130 kg/286 lbs. - Rulon Gardner, Afton, Wyo., (Sunkist Kids)  - won dec. Sergei Bosketov (Russia), 8-0; won by tech. fall over Alexander Kuznitzov (Russia), 11-0, 2:59    Head Coach - Dan Chandler, Minneapolis, Minn.    Assistant Coach - Rob Hermann, Pensacola, Fla.    National Greco-Roman Coach - Steve Fraser, Colorado Springs, Colo.