Seattle Slew left his speed in the East and lost, for the first time, Sunday at Hollywood Park. Forego failed Monday under 138 pounds in the Suburban Handicap at Belmont Park.It has been a long time since two such healed favorites were beaten back-to-back on a holiday weekend.

There was, however, an important difference in their losing.

Forego lost for all the right reasons, falling a neck short after trying to concede Quiet Little Table 24 pounds over 1 1/4 miles. His performance only reinforced the belief that winning the Triple Crown for 3-year-old is merely difficult: winning the Handicap Triple Crown is almost impossible.

The Suburban is the middle event in the Handicap Triple, a three-race set Forego has been trying to put together for four seasons during his reign as Horse of the Year. So, although 138 pounds represented an awesome assignment, Forego's people had little choice but to have their 7-year-old gelding go postward.

Perhaps, next year, Eddie Maple can be induced by Forego's folks to stay out of the series. The jockey beat Forego in the 1974 Metropolitan with Arbees Boy, in the 1976 Suburban with Follish Pleasure and Monday with Quiet Little Table, a mount he picked up the morning of the race after Co Host was scratched because of a minor injury.

No matter. Forego lost no stature in surrendering to gamely to a lightweight.

Seattle Slew's appearance in California was something else.

Hollywood's Swaps Stakes, despite its $300,000 purse tag, was the wrong race at the wrong time for the Belmont-based colt, which on June 11 had become the first undefeated Triple Crown winner. The Swaps was a race too far, in terms of geography and certainly in terms of contemparary racing history. It also probably was a race too soon, coming three weeks after the Belmont Stakes.

When Seattle Slew's people came to the press box following the Belmont they assured and racing world their colt would be given a vacation. He had earned it, they said, and he needed it.

A week later we were told Seattle Slew had lost only 10 pounds in completing his perilous spring and summer jaunt from Florida to New York to Kentucky to Maryland and back to New York. Instead of being rested, Seattle Slew was sent West, where a very good colt, J. O. Tobin, was waiting.

I have no criticism of California racing or California race tracks. The sport is healthier there than in any other state, and the California fans deserve to see the best horses such as Forego and Seattle Slew.

But when will Eastern owners learn that California stakes can no longer be won as an after-though? The competition is tough.And there is something about the sudden change of scenery, when a horse goes over the Rockies that seems to do him little immediate good.

Seattle Slew's people made a tremendous mistake in judgement. If they were determined to have their horse run again so soon the proper place this July Fourth weekend was Belmont Park, at home against Forego in the Suburban. The weights never would have been better for the 3-year-old.

Why is it, after a string of successes, owners often come to believe their champion thoroughbred can achieve anything asked of them? The owners begin to believe all the stuff and nonsense written about their brave charges, about "super horses" which, unfortunately, are made of the same flesh and blood as the horses they've beaten.

Had Seattle Slew won in California Sunday the next act scheduled for him might well have been to walk on Puget Sound during his excursion to Long Acres in Seattle.

His owners know better, now. They learned the hard way, by seeing Seattle Slew embarrassed by 16 lengths in a race in which he had so little to gain. The $194,900 first money was a pittance compared to the millions lost in potential syndication value.

Seattle Slew never has been as exciting as Secretariat. But he was underfeated. That was his great attraction. Now he faces a difficult summer and fail. J. O. Tobin may come East to challenge him in the Travers at Saratoga Aug. 20. Forego awaits them both, at weight-for-age, in the Woodward Malboro and Jockey Club Gold Cup during September and October.

By November, Seattle Slew's reputation may be seriously tarnished. If so, the owners have only to remember the words they uttered a few hours following the Preakness at Pimlico this spring.

"A horse like Seattle Slew, who is so superior, gets beaten only because of the people around him making poor judgments," Jim Hill observed.

After being beautifully managed through nine races, Seattle Slew's brain trust made a classic boo-boo in sending the colt West for the swaps. They should have challenged Forego in the Suburban or the Brooklyn Handicap, then gone to Paris for the Arc de Triomphe.

That way, there would have been everything to gain and comparatively little to lose