SPORTS ON WEEKEND TV : Rams in Preseason Debut

Two is the magic number for television sports fans this weekend, with that number of anticipated NFL exhibition debuts, Dodger baseball games and days of coverage of three golf and tennis tournaments.

Football: Seeking to bounce back from their 5-11 record of 1990, their most losses since 1962, the Rams open exhibition play against the Atlanta Falcons at 5 p.m. today on KCBS Channel 2. Former USC quarterback Todd Marinovich is expected to see his first NFL action when the Raiders face the Miami Dolphins in Tokyo. Channel 9 and ESPN (cable) will air tonight’s game at 7 p.m. Other NFL telecasts will match the San Francisco 49ers and Chicago Bears (today, 10:30 a.m., Channels 4, 36 and 39); Houston Oilers and San Diego Chargers (tonight, 11:30 p.m., Channel 10) and Washington Redskins and Pittsburgh Steelers (Sunday, 5 p.m., TNT).

Baseball: The best in the National League West meets the worst, as the division-leading Dodgers visit the Houston Astros, with KTTV Channel 11 providing the coverage today at 5 p.m. and Sunday at 11:30 a.m. The NL East-leading Pittsburgh Pirates will play the St. Louis Cardinals today at 10:15 a.m. on Channels 2 and 8. ESPN’s 5 p.m. Sunday telecast will pit the streaking San Francisco Giants against the struggling Cincinnati Reds.

Golf: All three tours are on the air this weekend. The PGA stops at Grand Blanc, Mich., for the $1-million Buick Open (today and Sunday at 1 p.m., Channels 2 and 8). The seniors tee off in the $450,000 Northville Long Island tournament (today at 11 a.m., Sunday at 10:30 a.m., ESPN) while the women will compete in the $500,000 Phar-Mor in Youngstown, Ohio (today at 1 p.m., Sunday at 12:30 p.m. ESPN).

Tennis: Viewers with the right combination of cable services and a knowledge of Spanish can watch semifinal and final coverage of three tournaments. The $225,000 Volvo Tennis/Los Angeles will air today at 1 p.m. and 7:30 p.m. and Sunday at 4 p.m. on Prime Ticket. The women’s $225,000 Mazda Tennis tournament will be telecast in Spanish at 3 p.m. today on Channel 34 and in English Sunday at 2 p.m. on ESPN. Another men’s tournament, the $200,000 U.S. Pro Tennis Championships, will be seen today at 10 a.m. and 7 p.m. and Sunday at 10 a.m. on SportsChannel.

Other Sports: Hot on the heels of the little-watched and financially disastrous U.S. Olympic Festival comes another multi-sport extravaganza, the Pan American Games. This weekend’s coverage includes basketball, diving, gymnastics, swimming and track and can be seen today at noon on Channel 10; 1 p.m. on Channels 7, 3 and 42 on “Wide World of Sports”; at 3:30 p.m. on Channel 10; at 4:30 on Channels 7, 3 and 42; Sunday at 3 p.m. on TNT, and 4 p.m. on Channels 7, 3, 10 and 42.