Russell wreaked havoc in the heart of the order, going 4-for-5 with a homer, two doubles, two RBIs and three runs scored. Along with Happ's three single and a double, the game marked the first time since at least 1913 that the Cubs have had two players aged 23 or younger collect four or more hits in the same game.
"Addison looks really comfortable. I know you see it up there also," Cubs manager Joe Maddon said. "And Happ, when he starts making contact, he keeps making contact. And I like it from the right side. That's very large that he's starting to do it from the right side."
Considering Chicago's lineup is missing Jason Heyward and Ben Zobrist due to injury, and Kyle Schwarber was just sent down, Russell's and Happ's big games were welcomed signs for a Cubs offense that ranks 29th in the Majors in hitting (.239) and averaged three runs per game in its last series against San Diego.
Thursday marked the second game in a row and third time in the last week that Russell hit cleanup.
Maddon knows the club will need his bat down the stretch. The manager said the 23-year-old, who's hitting .382 with eight extra-base hits over his last 34 at-bats, has swung at fewer pitches out of the zone of late.
"He drives in runs. He did that last year," Maddon said. "If you get guys on base, he's going to give you as good of an at-bat as anybody in that lineup. He showed that last year. Almost 100 RBIs ."
And if Happ can produce the way he did behind Russell, there's no telling what the ceiling is for this Cubs attack, especially with Anthony Rizzo and Kris Bryant hitting ahead of them.
"We did a great job in the middle of the order of driving in runs," Happ said. "It helps when you don't scatter the hits. It helps when two guys get four hits back-to-back."
Patrick Pinak is a reporter for MLB.com based in Miami who covered the Cubs on Thursday.