Pittsburgh padded its lead in the eighth inning, when infielder Chris Bostick and catcher Jin-De Jhang ripped back-to-back home runs to right field.
The Pirates struck first, as McCutchen doubled and came home on Polanco's single off Gabriel Ynoa in the first inning. Ynoa retired all three hitters he faced in the second.
"In the first inning, I was going too quick towards home plate," Ynoa said through a translator. "In the second inning, I was more calm, under control."
The Orioles tied it up in the fourth on Anthony Santander's RBI single off Pirates setup man Daniel Hudson, driving in Adam Jones, who doubled.
Second baseman Alen Hanson, competing for an Opening Day roster spot, drove in Polanco in the fourth with a sacrifice fly to center. Polanco tacked on another run in the fifth with an RBI single to right.
The Bucs ran out two pitchers competing for the fifth spot in their rotation, Steven Brault and Trevor Williams, followed by most of their projected Opening Day bullpen: closer Tony Watson, Hudson, setup man Felipe Rivero, Juan Nicasio and Antonio Bastardo.
"It's awesome to get back on the mound and face other hitters. It was cool that I got to face the Orioles," said Brault, who was drafted by Baltimore. "That makes it extra fun. We started. It's baseball season now, so it's an exciting time."
Orioles Up Next: Left-hander Wade Miley will make his spring debut on Sunday when the Orioles host the Pirates in Sarasota, Fla. First baseman Chris Davis and outfielder/designated hitter Mark Trumbo, who led the Majors in homers last year, are expected to make their 2017 Grapefruit League debuts. First pitch is scheduled for 1:05 p.m. ET.
Pirates Up Next: The Pirates will make the short trip to Sarasota on Sunday for a rematch with the Orioles at Ed Smith Stadium. Right-hander Jameson Taillon, looking to build off an impressive rookie campaign, will start for the Bucs. McCutchen is expected to start in right field, with top outfield prospect Austin Meadows playing center. First pitch is scheduled for 1:05 p.m.
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