The field of some 300 wrestlers was narrowed after the first day of competition at the 17th annual ASU/Sunkist International Open wrestling tournament in Phoenix, Ariz.     A total of 305 wrestling are competing in this year's competition in Freestyle, Greco-Roman and Women's Freestyle, including athletes from the United States, Canada, and Puerto Rico. For the first time, the tournament is offering cash prizes awarded to the top three wrestlers in each weight class. Champions will each receive $1,000, with second place and third place finishers earning $500 and $250, respectively.    They key weight class to watch on the Greco side is 58 kg., where the field includes 2000 Olympian and 2001 World Team member Jim Gruenwald, former World Champion Dennis Hall, and 2001 Junior National Champion Cam Jones     Cam Jones (USA) tech falled Marlos Jeantete (USA), 12-0 in 1:14 and won by injury default over Camilo Gonzalez (USA) to advance out of his pool.    James Gruenwald (USA) tech falled Steven Szilva (USA), 10-0 in 1:43 and Erin Kowal (USA), 10-0 in 3:52 to win his pool.    Dennis Hall (USA) tech falled all the opponents in his weight class, including Willie Madison (USA), 12-0 in 1:08; Mervin Ford (USA), 11-1 in 1:32; and Jose Nieves (USA), 12-0 in :45.     Jones will face Gruenwald in the semi finals, while Hall's semi final opponent has not yet been determined.    The 69 kg. freestyle weight class also has the potential for an exciting final. Both 2001 Olympic Champion Daniel Igali of Canada and 2001 World Team member Chris Bono (USA) have advanced to the semi finals.     Daniel Igali (CAN) tech falled both his pool opponents, including Andrew Shuler (USA) in :42, and Dana Holland (USA), 10-0 in 1:56. The defeated James Medeiros (USA), 10-2 in the quarter finals to advance to the semis where he will face Neal Ewers (CAN).    In pool competition Chris Bono (USA) defeated Danny Brown (USA), 6-2 and tech falled Joey Ortiz (USA), 12-1 in 5:25 to win his pool. In the quarter finals Bono won a 6-0 decision over Chris Ayers (USA) to advance to the semi finals where he will face Jason Peters (USA).     A total of 68 women are competing in the Women's Freestyle competition this year, including 2001 World Team members Stephanie Murata at 51 kg.; Sara McMann at 62 kg.;  and Toccara Montgomery at 68 kg..     Murata tech falled both her pool opponents, including Catherine Migita (USA), 11-0 in 1:50, and Danielle Hobeika (USA), 10-0 in 3:42, to advance to the semi finals.    Pool competition for Sara McMann (USA) will continue today. McMann had two matches yesterday incuding a fall over Peggy Vandemark (USA) in 1:02; and a fall over Emilee Murphee (USA) in 2:36.    Toccara Montgomery (USA) also will continue pool competition today. Her one match yesterday resulted in a fall over Meg Dolan (CAN) in 1:27.    Competition resumes again at 9 a.m. Sunday, Oct. 28.