Chen escaped a jam in the top of the sixth today after Paul Konerko doubled with one out. Darren O'Day and Francisco Rodriguez were warming in the bullpen.
The writing was on the wall.
Chen, with his pitch count at 99, wouldn't return for the seventh. He also won't get the win because the Orioles continue to squander opportunities to break a 2-2 tie.
The Orioles are 1-for-11 with runners in scoring position and have stranded eight.
Pinch-hitter Nate McLouth doubled with one out in the sixth, but was thrown out at third on Chris Snyder's grounder to short. Brian Roberts struck out. End of threat.
O'Day replaced Chen in the seventh. End of start.
O'Day is making only his second appearance since Aug. 28, and his first since Sept. 1.
Chen turned in his 13th quality start by allowing two runs and six hits in six innings, with no walks, eight strikeouts and one home run. This is the fifth time that he hasn't issued a walk.
Chen had surrendered 11 runs and 12 hits in his last two starts over 7 2/3 innings.
J.J. Hardy committed an error with one out in the seventh, only the 41st for the Orioles in 141 games.
Update: The White Sox brought in a left-hander, David Purcey, to work the bottom of the eighth. Danny Valencia was leading off.
Didn't they get the memo?
Valencia doubled for his third hit of the day and took third base with one out on an errant pickoff throw by catcher Josh Phegley. McLouth reached on an error by second baseman Leury Garcia, who began the day in center field, to put runners on the corners.
Matt Wieters pinch-hit for Chris Snyder and struck against right-hander Nate Jones. McLouth stole second as Wieters went down swinging with the count full.
Roberts grounded out to second, making the Orioles 1-for-16 with RISP. They've stranded 11.
Jim Johnson will pitch the ninth.
Update II: Pinch-hitter Conor Gillaspie homered off Tommy Hunter with one out in the top of the 10th, but the Orioles scored twice in the bottom half on Wieters' two-out walk-off single to take a wild 4-3 victory over the White Sox.
Henry Urrutia, pinch-hitting for Casilla, singled with one out in the bottom of the 10th and pinch-runner Chris Dickerson raced to third on Nick Markakis' bloop single to left, the ball falling inside the left field line. McLouth struck out looking at Addison Reed's eighth pitch of the at-bat, but Markakis stole second on the play.
Wieters lined a single into right field and pumped his fist as he rounded first. The Orioles went 2-for-18 with RISP, stranded 12...and won.
Hunter has allowed nine homers in 59 appearances.
Jim Johnson retired the White Sox in order on nine pitches in the top of the ninth inning.
The Orioles improve to 76-65 overall, 7-5 in extra innings and 16-25 in one-run games. They've won three straight for the first time since Aug. 6-9.