When Warner Amex signed a five-year contract to carry Pirates baseball on pay-TV (60 games this season) on its Pittsburgh channel, it threw in a pledge to buy 100,000 tickets. Mere prelude.

Warner Communications, joint owner with American Express of the Pittsburgh cable television franchise, now will buy 48 percent interest in the team.

The John W. Galbreath family, principal owner for 33 years, will retain controlling interest, 51 percent, of a club that, despite regular stature as an NL East contender, has lost heavily: 1982 attendance barely passed 1 million while the salaries of three players (Parker, Madlock, Thompson) each approximate $1 million a year. With Warner's capital investment, its media resources and the recent deal whereby the team turned over operation and maintenance of Three Rivers Stadium to the city, which is refurbishing it, it could be make or break for the Pirates in Pittsburgh.

Who has more clout than television?

Warner, Horner. Atlanta's Braves figure on clout at third base for years to come--Bob Horner accepts $1 million, $1.2 million, $1.5 million, $1.8 million in a 1983-86 contract. His agent says it makes him the game's highest-paid 25-year-old ever. After the Braves took Horner off the trading block, says agent Bucky Woy, "I wanted to grab a chunk of the money before Dale Murphy got it." Center fielder Murphy, the National League MVP, is yet unsigned . . .

Spring training camps can open Feb. 17 for pitchers, catchers and players coming off injuries, and all players may be invited to come out as early as Feb. 22, but no team can be forced to report before March 1. That's the agreement just reached between players association and majors, after the union threatened to keep all members away until March 1--outgrowth of last winter's "request" by George Steinbrenner for some of his Yankees to report a week early, Feb. 10 . . . Seattle's Mariners want to see if Clint Hurdle, ex-Royals and Reds, is through at 25; invite him to camp . . .

Ron LeFlore, White Sox outfielder, faces hearing Feb. 8 over the Sept. 30 drugs/gun bust in his Chicago apartment. A plea for dismissal was rejected by the judge yesterday--two days after LeFlore lost a 6-week-old son by sudden infant death syndrome.