How it happened: Rick Porcello, who authored a quality start in each of his first two outings, joined the ranks of Clay Buchholz, Justin Masterson and Wade Miley as Red Sox starters with a woeful performance to their name in the past week.
Porcello allowed eight runs on 12 hits, walking four and striking out six in his five innings of work. The 12 hits allowed tied a career-high for the right-hander, who simply didn't have his best stuff from the get-go of this one.
Home runs by Adam Jones in the first inning and Ryan Flaherty in the second got the Orioles off to a fast start as the long ball continues to prove problematic for Porcello. The two homers brought his season total to five allowed in 18 innings pitched.
Despite getting himself out of a bases-loaded, one-out jam in the fourth with a 1-2-3 double play, Porcello didn't enjoy the same success in the fifth. With the bases once again loaded, Travis Snider singled in a run, followed by Manny Machado driving in another with a sacrifice fly.
Sent back out for the sixth inning, Porcello loaded the bases again on a hit by pitch and two singles before Jones (who tied career-highs with four hits and five RBIs) cleared the bases with a double, ending Porcello's day.
Through their first 12 games of the season, Red Sox starters have the worst ERA in the league with a combined mark of 6.24. Only Joe Kelly -- the team's No. 5 starter -- has an ERA under six.
A three-run home run by Hanley Ramirez in the first inning was the only offense the Red Sox mustered, as they left seven runners on base in the loss.
Ortiz ejected: Taking exception to a called strike by third base umpire Jerry Meals on a checked swing in the fifth inning, Red Sox designated hitter David Ortiz was ejected from Sunday's contest by home plate umpire John Tumpane.
Ortiz, who was tossed after exchanging words with Meals, gave an earful to Tumpane before tossing both his bat and arm brace on the ground near home plate and proceeding back to the dugout.
Daniel Nava came in to inherit Ortiz's 1-2 count and grounded out on the first pitch he saw.
Panda power: In his 52nd plate appearance this season, Pablo Sandoval finally notched his first extra-base hit as a Red Sox with a double off the Monster in the eighth inning.
Up next: The Sox will hope to split the series Monday morning in their annual 11:05 a.m. ET game on Patriots Day. Masterson will toe the rubber for Boston, opposed by Orioles left-hander Wei-Yin Chen.