Those two thoroughbreds, Seattle Slew and Steve Cauthen, demonstrate that you can't keep a good horse or a good jockey down.

Slew, who looked burned out in that decisive California defeat following his Triple Crown success, has been reveling Turner Jr. was quoted the other day. "If Slew gets to feeling any better, he'll be jumping over these trees." He'll likely run in a stakes race or two at Aqueduct in October before coming to Laurel for the International in November, then moving to Florida for a winter campaign . . . Cauthen, 17, raised New York eyebrows sith a "slump" this week, blanked three straight days on a streak of 26 consecutive losers. But the lad who broke all the records, as an apprentice bounced back yesterday to capture the second and fourth races, giving him 71 wins as a journeyman jockey in 380-plus starts to go with his 284 winners before he lost his "but" (weight allowance). A ton of other in-the-money rides show he's lost no desire or ability since that spill racked him up for several weeks of the summer . . .

Oodies of us in the sports and media community are rooting for a comeback by Mare Splaver, the classy public relations director of the Bullets - classy enought to have been offered the P.R. directorship of National Basketball Association HQ in New York last year, and to have turned it down to stick with the Capital Centre family. Splaver rallied from six weeks in a GW Hospital bed with leukemia this summer, got home and came through with thanks to his legions of visitors and well-wishers in his "Top of the Key" column in the Centre's monthly. "Good Times." But now he's back in the hospital - come on, Splave . . .

Rep. James Santini (D-Nev.). a former judge in Las Vegas, is pushing for Congress, via the House subcommittee of which he is a member, to investigate the NCAA for its sanctions against UNLV's basketball program and coach Jerry Tarkanian. "Bloody arbitrary . . . star chamber" Santini rails against the association for pinning the school with two years probation and putting it on notice to take action (suspension, perhaps) against Tarkanian . . .

Sadaharu Oh: still 755 HR. Last night before anotehr Tokyo full house of 50,000, the Yomiuri Giant grounded out, doubled, then walked boo twice . . .Former Met problem Dave Kingman isn't doing much better playing out his option in the late, late box scores than he did in the East but insists on maybe quadrupling his $73,000 pay. So the San Diego Padres put the tall swinger (222 with 20 HR) on waivers this week - just to see who's interested. "We have no intention od releasing him," said Padre owner Ray Kroc: but as for his salary demand, "If Kingman goes all the way to the moon, he isn't going to get it" . . . Bigger hitters are the Baltimore Monuments. They went into the pro slow-pitch softball playoffs in Cincy last night with two of APSPL's top 11 hitters in John Copenhaver, .599 and Boom Boom Hutcherson, .596. Hutcherson is tied for eighth in home runs (45) and third in RBI (129) behind Chicago's Benny Holt (89 HR, 187 RBI in approximately 55 games) and Detroit's Ronnie Ford (83 HR, 180 RBI) . . .