Richie Palacios hit his third homer in two games, five St. Louis pitchers held Baltimore to three hits and the visiting Cardinals defeated the Orioles 1-0, taking the final two games of a three-game series.
Drew Rom (1-2), an Oriole minor-leaguer when he was sent to the Cardinals as part of the Jack Flaherty trade last month, emerged with his first major league win. He went 5 2/3 innings and allowed two hits and three walks while striking out seven.
Casey Lawrence (two-thirds of an inning), Giovanny Gallegos (one inning) and John King (one inning) provided scoreless relief, and Ryan Helsley worked the ninth for his 10th save. Baltimore's Gunnar Henderson tripled with two outs in the ninth, but Helsley got Aaron Hicks to pop out.
Baltimore starter Kyle Gibson (14-9) allowed one run on three hits over 6 2/3 innings. He walked three and struck out four.
The Orioles (91-54) lead Tampa Bay (90-57) by two games in the American League East. The Rays visit Baltimore for a four-game series beginning on Thursday.
After scoring 10 or more runs in four of five games, Baltimore has scored a total of two in the past two contests while going a combined 1-for-18 with runners in scoring position.
Baltimore first baseman Ryan Mountcastle left the game in the third inning due to left shoulder discomfort.
Palacios broke a scoreless tie with two outs in the fourth when he hit a first-pitch fastball from Gibson over the scoreboard in right for his fourth homer of the season.
The Orioles had runners on first and second with one out in the sixth. Anthony Santander doubled to knock Rom out of the game, and Austin Hays drew a walk from Lawrence. Jordan Westburg then lined out to left, and Henderson flied out to center.
St. Louis (65-81) got a walk and a single with two outs in the eighth, but DL Hall struck out Tyler O'Neill to end the threat.
Ramon Urias walked with one out in the Baltimore eighth, but King got Santander to ground into a double play.
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