MIAMI, FEB. 27 -- In a surprise move, the Baltimore Orioles threw their youth movement into a higher gear this morning by trading veteran third baseman Ray Knight to Detroit for left-handed pitcher Mark Thurmond.

The trade means rookie Craig Worthington, the organization's No. 1 prospect, will get a full-blown shot to win the third-base job. Worthington, 22, had been expected to compete with Knight, but now will have to fight only his own inexperience and the Orioles' high expectations.

If he wins the job, he would be a starter on what is shaping up to be a very young team. After today's trade, an Orioles official said: "I guess we're the Baby Birds now."

With the first exhibition game a week off, the Orioles could open the season with a starting eight that includes four players with one season or less of major league experience -- second baseman Bill Ripken (23), left fielder Pete Stanicek (24), center fielder Ken Gerhart (26) and Worthington (22).

The trade also means the long search for a left-handed reliever might be over. Although Thurmond has started most of his career and has been less than effective as a reliever, he's almost certain to wind up in the bullpen.

"We've looked a long time for a left-handed reliever," Manager Cal Ripken Sr. said. "It gives you a chance to make some moves late in the game, and it may also keep the other team from making a move."

Thurmond, 31, was 0-1 with five saves and a 4.23 ERA for the Tigers last season, but pitched very little near the end of the season as Sparky Anderson used Mike Henneman, Willie Hernandez and others. His best season was 1984 when he was 14-8 with a 2.97 ERA as a starter for the National League champion San Diego Padres.

"We had to use him as a reliever, but he's really a starter," Detroit General Manager Bill Lajoie said. "He's more a control-type pitcher, not a guy who is going to come in and strike out the side."

It's unlikely he would wind up as a starter for the Orioles, who already have 10 pitchers competing for five spots.

The more intriguing part of the trade involves third base, a position that has been in flux since Doug DeCinces was traded after the 1981 season. In the six seasons since, 24 people have played the position.

Despite only three seasons of professional baseball -- including one above Class A -- Worthington might be their man, the Orioles believe. He's considered excellent defensively and, despite a terrible start, finished with a .258 batting average at AAA Rochester last season.

He would have played third for the Orioles last September, but tore a hamstring Aug. 14.

"He was just starting to get adjusted," Ripken Sr. said. "I don't think he was overmatched, and I was looking forward to seeing him even before this trade."

But Ripken said he would consider other options. If Worthington can't hit, the No. 1 candidate for the job would be Rene Gonzales, a good-field, no-hit player who was used sparingly last season.

Ripken said he would consider moving one of his sons to third and would experiment some during spring games. If Cal Ripken Jr. plays third, Jackie Gutierrez or Gonzales would be used at short. If Bill Ripken is moved to third, Stanicek would be used at second.

That would appear to be a last resort. Even as he talked about the experiments, Ripken Sr. said his sons formed a double play combination "as good as any in the American League," and it's unlikely he would break up that combination.

Worthington accepted the challenge, saying: "I'm really excited. I don't know what they're going to do, but if I can show them I can play; I'll be in there. I feel I can do it."

Knight, 35, hit .256 with a career-high 14 homers in his only season with the Orioles, and while he accepted his new situation today he may not like it once he arrives in Lakeland, Fla.

Detroit Manager Sparky Anderson, who was Knight's first manager when both were in Cincinnati, said today he would use Knight as both a first baseman behind Darrell Evans and a third baseman behind Tom Brookens and Jim Morrison. Knight may also be used at designated hitter, but Anderson figured his total at-bats might be "between 250 and 300."

Anderson added: "Ray will not like that. He lives to play, but he'll understand. He'll be really good for this team."

Knight and his wife, pro golfer Nancy Lopez, didn't arrive in Miami until late Friday, then spent part of the evening unloading a U-Haul-It. He arrived at Miami Stadium a little after 9 this morning and was asked to see General Manager Roland Hemond, who greeted him with: "Good to meet you, Ray. You've been traded to Detroit."

"It's hard to think about the baseball part of it right now," Knight said later. "I'm here with my two daughters, and they've both got the flu. Nancy was supposed to fly to Hawaii tomorrow to play golf, so it's not a great time."

Thurmond welcomed the trade because it means a chance to pitch. Not only was he unable to break into one of the best starting rotations in the game, he wasn't used much in relief after Henneman's emergence last season. Today, he said he'd accept a bullpen job, but hopes to get a chance to start.

"I like Detroit," he said, "but I didn't like my role at all. Last year, I did not say anything because this is a team game. For every six times I warmed up last season, I'd get in once. But we had success, so I didn't complain. I'd like to start again. It's just that they have the best pitching staff in the league here. I think there are openings in the rotation at Baltimore."