BALTIMORE, JULY 20 -- Six years ago, trainer Ron Alfano appointed then-apprentice Donald Miller Jr. his No. 1 jockey, and his racing stable became one of the most successful in Maryland. Last month, Alfano and Miller tried a new tack in the interest of progress: they split up.

The decision essentially was mutual. Alfano sought to revive what recently had become a struggling stable; Miller, whose commitment to Alfano at times suffocated outside assignments, sought to enrich his clientele.

Now, nearly three weeks into Pimlico Race Course's summer/fall meeting, the change in prescription is producing positive effects. Alfano leads trainers with 10 victories in 33 starts, and Miller is second to apprentice Kent Desormeaux, the country's top race-winning jockey.

"Donnie's a great rider, always has been," said Alfano, Pimlico's premier trainer in 1986. "But I think the way my barn was going the early part of this year, that it was best for him and me that I switch around. And it's not like I'll never ride Donnie; he's won a couple of races for me {at Pimlico}. I just wanted to stir things up a little bit.

"I don't see where he has slowed down at all. Donnie's always gonna win his share, no matter where he goes. He's in demand."

"It gives me an opportunity to ride for more people who I started out riding for -- a lot of little trainers," said Miller, the most consistent winner among Maryland jockeys before Desormeaux arrived last fall. "What made it tough was that a lot of trainers didn't want to have to sit second when Ronnie had first call, and you really can't blame them.

"But I'm an established rider; it's not that difficult for me to ride for the other people. It'll leave a lot more doors open for me."

The separation also cleared a path for Desormeaux and Mario Pino to tap Alfano's barn of 60 strong. It gives veteran Pino a third major stable offering regular mounts -- he is John Mobberley's primary rider and one of Scott Regan's top two.

All the business could present an interesting dilemma for Pino. "Lately, it hasn't come up when I've had conflicts over who to ride for," he said. "But who wouldn't want to make a tough choice like that. It's like deciding between two stakes horses."

Pino hasn't wasted his new opportunity: of the first 11 horses he rode for Alfano, he produced five victories, two seconds, one third.

"Mario and I are very different types of riders," Miller said. "Mario's a very good speed rider, and I tend to come from off the pace. {Alfano} trains his horses, basically, to sit just off the pace and come around. That's probably why we've done so well over the years, because he trains them the way I rode them. But recently, it seems like more of his horses need the lead to win."

Of his distinction as a speed rider, Pino said, "It's a matter of common sense; you've just got to save them as much as you can. Sometimes you've got to be strong with them, sometimes you've got to nurse them. And that's much more important {at Pimlico} than at Laurel, where speed is not too effective."

With the new system, Alfano customizes riding assignments, seeking a perfect fit between horse and rider.

"There are horses that maybe are frail or have been around a while," Alfano said. "You'd be looking to get the weight off those horses {i.e., use an apprentice jockey}. There are horses that you're looking for an aggressive rider, there are horses that you're looking for a patient rider. And there are a few riders here that fit the bill for those different kinds of horses.

"Mario's always been a top rider around here, and I thought he would fit some of those horses, so I took a shot. I just haven't had the opportunity to use him, and I'm finding that opportunity now. Naturally, you've got the leading bug boy {apprentice Desormeaux} in the country right here, too, so I'm trying to get him on a fair amount of horses."

Desormeaux, already receiving first call on mounts for trainers Barclay Tagg and Marvin Moncrief, tightened his grip as Maryland's most victorious jockey when he began riding for Alfano. Over Pimlico's 15 days this meeting, Desormeaux has 22 winners from 130 races, an average of nearly nine (of a possible 10) mounts per program. Miller is 13 for 74, and Pino, who ranks fifth, is nine for 79. Desormeaux "is no cinch to beat me this meet," Miller said.

All the movement around Alfano's stable illustrates racing's unpredictability: Miller departed, and Alfano's winning percentage perked up. Miller began riding more regularly for John Robb and Jim Murphy, and their stables became energized.

Robb (nine winners, 23 starts) is one victory behind Alfano.

"A few of the riders always felt that the only reason I did as well as I did was because I was riding for Alfano," Miller said. "And it hasn't been but for the last two years that it's been kind of a drag on my business -- other people wouldn't ride me because I was riding for him. So it kind of slowed me down a lot. Not on winners, but on the amount of horses I was riding.

"We split on good terms. He's a wonderful person, and I'm still riding for him. . . . This is workin' out better for everybody in the long run."