Seattle Slew and Run Dusty Run, the 1-2 finishers in the Kentucky Derby, arrived at Pimlico today for Saturday's Preakness Stakes in the same order.

Both were late, in terms of their ETAs. Slew, scheduled in about 1:30 p.m., did not get off the van from New York until 2:45 p.m. Dusty's flight from Louisville was delayed at the airport. Originally scheduled to be here at 2:30 p.m., he did not set foot in the back stretch until 6:45.

A length and three-quarters separated the favorite from the second choice at the end of the Derby. Seattle Slew again will be favored in the Preakness but Run Dusty Run is not likely to be second again in the wagering. That spot probably will go to Cormorant even though he was defeated by Iron Constitution by a hose Saturday in the Wthers Mile at Aqueduct. Coromant was seven for eight before that.

Seattle Slew, undefeated in seven races, was 1 to 2 for the Derby, going a mile and a quarter. The sun of Bold Reasoning looms 1 to 5 this weekend over a distance a sixtheenth of a mile shorter.

Fifteen horses competed at Churchill Downs. Only seven are set definitely for the middle event of the Triple Crown series. They are Seattle Slew, Cormorant, J. O. Tobin, Run Dusty Run, Counter Punch, Sir Sir and Regal Sir, the last having joined the lineup today when word was received from Canada of plans to ship the colt to Maryland Tuesday. Chris McCarron will ride Regal Sir.

Iron Constitution and Nostalgia remain possible additions to the field. Sandedrin, third in the Derby, definitely is not coming, trainer Lou Rondinello declared today.

Seattle Slew appeared to have vanned well from Belmont Park, where he worked a snappy seven furlongs in 1:24 4/5 Sunday morning. The colt will blow out of the Preakness Thursday.

"I don't know who is going to be the one to try to hook him Saturday," Glenn Ballenger said this morning, "but it won't be me. I want to let somebody elso do the dirty work."

Ballenger trained Counter Punch, a longshot owned by octogenarian John Hughes. Counter Punch has posted three firsts, one second, and three thirds in seven starts this season. In his most recent outing the gelding ran second in the Woodlawn Stakes here.

"Iron Constitution finished third that day, so I guess that's all the license we need in order to enter," Ballenger commented. "I've never tested Counter Punch as far as a mile and an eighth but he's a competitive little fellow and I have hopes for him even though we're stepping pretty far out on a limb."

Gregg McCarron, Chris' older brother, again will ride Counter Punch, undoubtedly from off the pace.

"This is the best male horse I've ever trained or Mr. Hughes has ever bred," Ballenger declared. "Mr. Hughes is a retired Chicago lawyer. He's in California now, but he's been in racing since the '30s, with a farm near Middleburg (Va.), and he's carried it the hard way, through good times and bad. He has only 17 mares now; he once had 104 horses on the place and wondered how he got that many."

Counter Punch is by Reverse out of a Citation mare.

"That's Calumet breeding on both sides," Ballenger noted. "Mr. Hughes has always been partial to Man o' War blood." Calumet, of course, has fared famously over the years in Triple Crown competition, but the trainer realizes that Counter Punch faces a tremendous task Saturday.

"Let's just say our horse will be in there pitching," Ballenger said. "He can be rated. He's a nice, quiet horse who doesn't figure to get all stirred up by the big crowd, and he can run both ways, early or late. I think he'll give a decent account of himself."