When the old man told him about the game, the kid immediately had ideas. First, he would be a star.

"I told Dad I'd take Willie Wilson out if he slid into second," Billy Ripken said. "He looked at me and said, 'By the time you get in the game, Willie Wilson will be long gone.'

. . . Then I thought about writing a book. It would be called 'One Day in the Big Leagues.' I figured I had the right name for it. People would want to know what Cal Jr. is really like. They'd want to know how much milk he really drinks. I'll just put it in the book, and they wouldn't have to ask."

He may not write a book and he may never play for the Baltimore Orioles again, but for one day, 21-year-old Billy Ripken did play in the big leagues.

He played second base for four innings this afternoon, alongside his brother Cal Jr., the Orioles' shortstop, and he played for his dad, Cal Sr., who was the Orioles' manager in a split-squad 8-3 exhibition loss to the Kansas City Royals.

If the day was exciting for the two older Ripkens, it was more so for Billy, who was invited from the Orioles' minor league camp to fill out the split roster. He came to bat only twice, grounding out in the seventh inning and grounding into a fielder's choice in the ninth.

The big leagues might not have excited him this time, but the fact that he was playing -- without pain -- did. He may never be the second coming of Cal Jr., but if he doesn't stay healthy for an entire season, he won't even be able to be Billy.

He was an 11th-round pick in 1982, but since then, an assortment of injuries has limited his playing time each season. He never has hit much -- .244 is his season-high -- but the Orioles won't make a judgment until he plays an entire season.

In successive years, he has had tendinitis in his right forearm, a sore left shoulder, a broken index finger and a broken middle finger. Scouts privately say he never will hit as well as his older brother, but that he does have defensive skills that could get him to the majors. Today, though, was a day to pose for pictures and consider the possibilities.

The imagination doesn't have to be stretched far to see this combination together again. At 25, Cal Jr., is just beginning his career, while Cal Sr., 50, remains a serious candidate to manage the Orioles when or if Earl Weaver retires again.

"I'm proud of who I am," Billy Ripken said, "and I'm proud of my brother and dad. This is the first time we've ever had on the same uniform at the same time, and it's a fun day."

Right fielder Larry Sheets left the game in the the third inning after ramming the fence to get Steve Balboni's drive. Sheets' sore neck and shoulder and will be checked again Sunday . . .

In Miami, Storm Davis, Rich Bordi and Tippy Martinez pitched a four-hitter as the other half of the Orioles beat the Atlanta Braves, 3-0. Jim Dwyer's three-run home run provided the runs . . . The Orioles' exhibition record is 2-6.