The Orioles loaded the bases with two outs in the second on a double and two walks, but Manny Machado grounded into a force at second.
In the fifth inning, Dayan Viciedo hit a solo home run to center field off Orioles starter Wei-Yin Chen (7-7 , 3.82 ERA) to give the Sox their first lead of the series. It was Viciedo’s 12th home run of the season.
Brian Roberts hit a solo home run on the first pitch in the bottom half of the fifth to tie it 2-2. With runners on the corners and no outs, Santiago retired the next three batters to hold the tie.
Santiago allowed seven hits and two earned runs, walked two and struck out four in five innings. Chen went six innings, gave up six hits and two earned runs, and struck out eight.
Josh Phegley committed his second throwing error of the game on a pick-off attempt at second and second baseman Leury Garcia followed with a fielding error to put runners on the corners with one out in the eighth inning.
Sox reliever Nate Jones entered and retired the next two batters to hold the Orioles at bay.
Semien started at third base for the second time since being called up on Sept. 3 and Leury Garcia started in center field.
Sox right-hander Andre Rienzo (1-1, 5.03 ERA) and Orioles right-hander Bud Norris (4-1, 4.28 ERA) are the projected starters for the series finale on Sunday afternoon in Baltimore at 12:35 p.m. CT (CSN/WSCR 670).