There were very few upsets in the first session of the Dave Schultz Memorial International Championships, held at the U.S. Olympic Training Center in Colorado Springs, Colo.    There are 288 entries this year, including 102 men freestyle wrestlers, 95 men Greco-Roman wrestlers, and 91 women freestyle wrestlers.     The quality of the competition is also high. The field included five past World or Olympic champions, and a total of 20 past World or Olympic medallists.     Two rounds were held in women's freestyle and men's Greco-Roman, and one round was held in men's freestyle in the morning round. The second session begins at 4:00 p.m. MST on Saturday.    The 120 kg/264.5 pound division in Greco-Roman features a pair of  gold medalists: 2000 Olympic and 2001 World champion Rulon Gardner (Colorado Springs, Colo./Sunkist Kids) and 2002 World Champion Dremiel Byers (Colorado Springs, Colo./U.S. Army). Both won two matches on Saturday morning, and have captured their pool competition, moving on to the semifinals.    The most loaded weight class in the field is the 63 kg/138.75 lbs. women's division. It features a pair of multiple World Champions, Nikola Hartmann-Dunser of Austria and Kristie Marano (Colorado Springs, Colo./New York AC). Past World medalists in the division are Sara McMann (Colorado Springs, Colo./Sunkist Kids), Lene Aanes of Norway and Viola Yanik of Canada. All of these medalists were unbeaten in the morning session, except for Hartmann-Dunser, who lost to Yanik by pin.    The other past World champion in the field is Brigitte Wagner of Germany in the women's 48 kg/105.5 lbs. division. Wagner's top challenger could be Patricia Miranda (Colorado Springs, Colo./Dave Schultz WC), who was a World silver medalist in 2003.    Perhaps the biggest upset of a U.S. wrestler was the defeat of No. 2 ranked Mike Mena (Bloomington, Ind./New York AC), who was defeated by Matt Azevedo (San Luis Obispo, Calif./Sunkist Kids), 4-1 at 55 kg/121 lbs.    Another tough match in that division came in the second round, when No. 1 Stephen Abas (Fresno, Calif./Sunkist Kids) needed to come from behind to defeat Enkhtur Badamsaikhan, a Mongolian competing in the USA, by an 8-4 margin. Badamsaikhan led 4-2 in the second period, but Abas scored a takedown and an ankle lace to grab a 5-4 lead, then closed out the match with three more points.    The Dave Schultz International marked the return of 2000 Olympic bronze medalist Garrett Lowney (Appleton, Wis./Minnesota Storm), who has been injured since last year. Lowney pinned Brandon Ruiz (Colorado Springs, Colo./Elite) in 1:10 in his first bout.