Three U.S. freestyle won their pool competitions and advanced in the championship bracket at the respected Medved International Championships in Minsk, Belarus, March 30.    Winning their pool competitions were Mike Mena (Bloomington, Ind./NYAC) at 55 kg/121 lbs., Jamill Kelly (Colorado Springs, Colo./Gator WC) at 66 kg/145.5 lbs. and Byron Tucker, Norman, Okla. (Sunkist Kids) at 74 kg/163 lbs. All three wrestlers had perfect 2-0 records in their pools.    Four other U.S. wrestlers suffered a loss in their pool and were eliminated.    Daniel Cormier (Stillwater, Okla./Gator WC) defeated veteran Rolf Sherrer of Switzerland, 10-1 in his opening match at 96 kg/211.5 lbs., but lost his second match by injury default with an arm injury.    Also eliminated in their pool competitions were Danny Felix (Norman, Okla./Sunkist Kids) at 60 kg/130 lbs., Aaron Simpson (Tempe, Ariz./Sunkist Kids) at 84 kg/185 lbs. and  Markus Mollica (Boston, Mass./Dave Schultz WC) at 84 kg/185 lbs.     The competition concludes on Sunday.    MEDVED INTERNATIONAL CHAMPIONSHIPS  at Minsk, Belarus, March 30  U.S. results    55 kg/121 lbs.  - Mike Mena, Bloomington, Ind. (NYAC) - pin Alexander Sakula (Belarus), 4:07; dec. Ularbek Tuganbaiuulu (Kyrgyzstan), 6-5    60 kg/130 lbs. - Danny Felix, Norman, Okla. (Sunkist Kids) - dec. Alexandre Skroman (Latvia), 5-1; lost ref. dec. to Zelipkhan Guseinov (Russia), 4-4, ot    66 kg/145.5 lbs. - Jamill Kelly, Colorado Springs, Colo. (Gator WC) - dec. Ayan Ondar (Russia), 3-1; dec. Alexandre Kolyvanov (Russia), 7-0    74 kg/163 lbs. - Byron Tucker, Norman, Okla. (Sunkist Kids) - dec. Vadim Fliaga (Belarus), 9-3; dec. Oshak Boziev (Russia), 4-3    84 kg/185 lbs. - Aaron Simpson, Tempe, Ariz. (Sunkist Kids) - lost dec. to Majid Khodei (Iran), 5-0; dec. Oleg Kushnir (Ukraine), 7-6    84 kg/185 lbs. - Markus Mollica, Boston, Mass. (Dave Schultz WC) - dec. Andre Kachko (Belarus), 9-1; lost dec. to Aslan Sanakoev (Uzbekistan), 3-0    96 kg/211.5 lbs. - Daniel Cormier, Stillwater, Okla. (Gator WC) - dec. Rolf Sherrer (Switzerland), 10-1; lost by inj. dft. to Evgeni Zabello (Belarus)