How it happened: The Cubs got to Orioles starter Kevin Gausman for two runs in the third inning as Luis Valbuena tied a career high with his 12th home run of the season and Logan Watkins drove in another run with a base hit. Javier Baez crushed a ball onto Waveland in the fifth inning for his sixth of the season to extend the lead to 3-0. Nelson Cruz hit his 34th home run of the season to break up the shutout in the seventh as Jake Arrieta dominated his former team, sending the first 13 batters of the game back to the dugout without reaching. He lasted seven innings giving up just four hits, one walk and the Cruz home run. The Cubs got that run back in the bottom of the inning when Arismendy Alcantara drove home Chris Valaika with an infield hit after Valaika doubled to lead off the inning. Hector Rondon earned his 20th save of the season.
Key play: With the Cubs leading 2-0 in the fifth inning, right fielder Ryan Sweeney threw out Chris Davis at home after a Caleb Joseph single. The play was reviewed to make sure catcher John Baker wasn't blocking the plate in violation of the new rules this season and the call was upheld.
What it means: Arrieta said he had nothing to prove to his old team but he did anyway. Cruising through the first three innings is becoming the norm. It's taking him very little stress to get through opposing lineups that first time around. His issues actually stem from being in the dugout too long while the Cubs are scoring runs. It happened again in the fifth inning but this time he got out of a jam with some help from Sweeney. His ERA is now 2.53. Baez is doing what Baez does. The strikeouts might pile up one day but then he'll crush a ball the next. The at-bats are still decent when he doesn't swing way outside the zone. Alcantara is actually struggling more right now but that's expected as well. He struck out with a man on third and less than two outs in the third inning but got a run home in the seventh.
Pitching rotation: Rick Renteria hasn't declared who will take Edwin Jackson's spot in the rotation after the right-hander went on the disabled list on Thursday. With an off-day on Monday the Cubs can stay on schedule with Travis Wood pitching Tuesday in Cincinnati.