Baltimore's Storm Davis has rightly been labeled a hard-luck pitcher of late, having lost three of his last four starts before tonight's game despite a 2.61 ERA in those contests.

But facing Detroit on a 72-degree, cloudless night in Memorial Stadium before 21,523, Davis lost one almost entirely on his own, giving up nine of the Tigers' 15 hits in 3 2/3 innings in a 6-3 Detroit victory. Davis was not helped by the Orioles' bats, which managed only six hits.

The loss, the Orioles' seventh in nine games and fifth in a homestand six games old, dropped them to 35-27. They are 6 1/2 games behind AL East-leading Boston, which beat New York, 7-6. That is the furthest the Orioles have been off the lead all season.

Davis (5-7) threw 103 pitches during his short stint, allowing three earned runs and leaving with Detroit up, 4-0, in the fourth. Brad Havens and Rich Bordi pitched respectably in relief, but it wasn't enough as Randy O'Neal (1-3), making his first start of the season, threw a strong 6 2/3 innings for the Tigers.

O'Neal, who had last started a game Aug. 11, 1985, and had appeared in 16 games as a reliever, handcuffed Baltimore except for Larry Sheets' two-run homer in the seventh. He faced only one batter over the minimum in the first six innings. Willie Hernandez came on in the seventh after Sheets' homer and held the Orioles in check, giving up one run in 2 1/3 innings for his 11th save.

Hernandez gave up the run in the eighth and a one-out double to Eddie Murray in the ninth, but survived intact to give the Tigers their second straight victory over Baltimore.

Detroit struck early. Lou Whitaker singled to left to open the game. Whitaker tried to steal second, but looked to be out easily because catcher Rick Dempsey had called for a pitchout. However, shortstop Cal Ripken dropped the ball on the tag, and Whitaker was safe.

Dave Collins bunted Whitaker to third and Kirk Gibson then hit a home run to deep right-center, his fifth of the season and third since he came off the disabled list June 1. That gave the Tigers a 2-0 lead, and marked the ninth straight time Baltimore had fallen behind to open the game.

After Davis struck out Lance Parrish, he walked Darrell Evans and Dave Bergman singled. Davis got out of the inning without further damage as Alan Trammell grounded to Ripken.

Gibson got his second hit of the night in the third inning, a one-out single to center. Parrish's single put runners on first and second and got the Orioles' bullpen working. However, Davis again got out of trouble, picking off Parrish and striking out Evans.

Despite two hits in the bottom of the inning, Baltimore failed to score, mainly because of sloppy base running. John Shelby opened with the first hit off O'Neal. One pitch later, he was caught stealing.

After Rick Dempsey grounded out, Alan Wiggins singled but was picked off when first baseman Bergman pulled a variation of the hidden-ball trick. After Wiggins successfully made it back to the bag on a pickoff attempt, Bergman pumped his arm as if to throw to O'Neal but, instead, held the ball and tagged out Wiggins, who had left the base.

Detroit added two runs to its lead in the fourth with a two-out rally that knocked out Davis. Pat Sheridan walked and Tom Brookens, who hit the decisive three-run homer in Detroit's 5-4 victory Monday, rolled a broken-bat single through the infield's left side. Whitaker hit a single to left to score Sheridan and make it 3-0.

Collins then singled to right, driving in Brookens, and signaling the end of Davis, who failed to retire seven of the last nine batters he faced. Havens, a left-hander, relieved Davis and struck out Gibson to end the inning.

Detroit knocked out Havens in the sixth inning as Brookens beat out an infield hit, stole second and went to third on Dempsey's errant throw.

After Havens walked Whitaker, Detroit Manager Sparky Anderson sent in Larry Herndon to pinch hit for Collins. Baltimore Manager Earl Weaver, playing the percentages, called for right-hander Rich Bordi to face Herndon. Bordi struck him out and then got Gibson to ground to first baseman Eddie Murray to end the inning without any damage.

After Sheets' seventh-inning homer, his ninth of the season, Detrout quickly got the runs back. Brookens led off the eighth with a walk and stole second. Whitaker then tripled off the wall and, one out later, Gibson drove him in with a single to center for his third RBI of the game to make the score 6-2.

Baltimore scored a run in the eighth as John Shelby singled and Dempsey doubled him to third with one out. Pinch hitter Juan Beniquez hit a sacrifice fly to bring the tying run to the plate. However, Lee Lacy grounded back to Hernandez to end the threat. The Orioles also wasted a one-out double by Murray in the ninth.

Catcher/third baseman Floyd Rayford, batting only .154 in 37 games for the Orioles this year, has agreed to accept assignment. to Class AAA Rochester and will report to the Red Wings Wednesday, Rayford had the right to reject the assignment because he has three years-plus major league service. In his place, the Orioles will call up catcher Al Pardo.