CHICAGO — Ubaldo Jimenez looked quite comfortable in his second career relief appearance.
"He was pretty effective," manager Buck Showalter said. "I was glad to see that. It was a good opportunity to get him back out there. You almost treat it like a start."
Jimenez replaced Bud Norris (11-8) after a rain delay of 3 hours, 9 minutes. The right-hander, who has struggled in his first year with the Orioles after signing a four-year, $50 million contract, allowed three hits, struck out five and walked one in his first relief outing since his major league debut with Colorado on Sept. 26, 2006.
"He went out there and competed and battled and threw strikes," catcher Nick Hundley said. "He's still working like crazy. He's very tough-minded, tough mentally. For him to go out there and keep us in the game was impressive."
Justin Grimm (4-2) pitched 3 1-3 hitless innings, helping the last-place Cubs to their second straight win against Baltimore. Chris Coghlan capped Chicago's four-run second with a three-run triple, and touted rookie Javier Baez hit his seventh homer in the seventh, an opposite-field liner into the basket in right.
Coghlan was 0 for 15 with six strikeouts against Norris before he connected for his fifth triple of the season.
"I'd be lying to you if I didn't say I saw it," Cubs manager Rick Renteria said, referring to Coghlan's trouble with the veteran right-hander. "But all things being equal, the way he's been swinging the bat, I really thought he was going to have a good chance to do something today."
The Orioles had seven hits after they announced before the game that All-Star third baseman Manny Machado had decided to have season-ending right knee surgery. Machado hurt himself on an awkward swing against the Yankees on Aug. 11.
It's a difficult blow for Baltimore, which is in prime position for its first division title since 1997. It leads New York by seven games after the Yankees beat the White Sox 5-3 earlier in the day.
The Orioles swept a three-game set against the White Sox before crossing town for their first series at Wrigley since 2008. They lost 4-1 on Friday when Jake Arrieta pitched seven solid innings against his former team.
A day later, they were still trying to find their prolific offense.
"They pitched real well," Showalter said. "They made a lot of quality pitches. We couldn't string anything together."
Adam Jones hit an RBI double in the first and Norris helped himself with a run-scoring infield hit in the second. But the Cubs responded with four runs in the bottom half, grabbing the lead for good on Coghlan's two-out liner into the right-field corner.
After Baez struck out for the final out of the second, the umpires waved the players off the field while a storm front passed through the area. The crowd of 37,156 cheered loudly when the grounds crew successfully pulled the tarp over the infield, and there was more applause in the final innings of Chicago-based Jackie Robinson West's victory in the Little League World Series.
The big cheer for the grounds crew came after Tuesday night's game against San Francisco was called and then suspended after the workers had trouble covering the infield during a popup storm.
Orioles: Machado's 2013 season cut short by a similar injury to his left knee. He likely will return to Dr. Neal ElAttrache in the next week or so for the procedure on his right knee.
Cubs LHP Tsuyoshi Wada (3-1, 2.75 ERA) and Orioles RHP Miguel Gonzalez (6-6, 3.80 ERA) meet in Sunday's series finale. Wada signed with Baltimore in December 2011, but injured his elbow and never pitched for the Orioles. Gonzalez is coming up from the minors to replace Ubaldo Jimenez in Baltimore's rotation.
Jay Cohen can be reached at http://www.twitter.com/jcohenap