It proved to be one nice call by the rookie manager.
Justin Grimm (4-2) pitched 3 1/3 hitless innings after a rain delay of 3 hours, 9 minutes, helping the last-place Cubs win their second straight against the AL East leaders. Logan Watkins had two hits and two RBIs, 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 (11-8) before he capped Chicago's four-run second with his fifth triple of the season.
"I'd be lying to you if I didn't say I saw it," 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."
Coghlan, who is batting .304 with 22 RBIs in his last 51 games, said he appreciated the vote of confidence from Renteria.
"He's the man," Coghlan said.
Chicago will try Sunday for its first series sweep since winning three straight at Boston from June 30 to July 2.
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," Orioles manager Buck 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.
"It was a tough day today," said Norris, who had won his last three starts. "The big, long rain delay kinda hurt us. We just have to let this one go."
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: RF Justin Ruggiano was scratched due to left ankle soreness. He was replaced by Ryan Sweeney. ... RHP Brian Schlitter's rehab was transferred to Triple-A Iowa. The reliever was placed on the disabled list on Aug. 10 with right shoulder inflammation.
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.
RHP Jacob Turner, who was acquired in an Aug. 8 trade with Miami, will make his first start for the Cubs on Wednesday in Cincinnati. LHP Travis Wood starts the series opener against his former team, and RHP Jake Arrieta gets the ball in the finale of the three-game set on Thursday afternoon.
Jay Cohen can be reached at http://www.twitter.com/jcohenap