The Cubs say they never quit -- it's inscribed on their World Series rings -- and they mean it.
Russell hit a game-ending, three-run homer off Neftali Feliz in Chicago's four-run ninth, sending the Cubs to a 7-4 victory over the Milwaukee Brewers on Wednesday.
Russell's second homer of the season helped Chicago take two of three from Milwaukee after dropping the series opener Monday. The Cubs trailed 5-0 on Tuesday night before rallying for a 9-7 victory.
"That's the type of style that we play," Russell said. "We feel strongly about that. It seems like whenever your count us out, we seem to have a spark."
The Cubs overcame a rough outing for right-hander Kyle Hendricks, who tied his career-high with four walks in five innings. Mike Montgomery, Pedro Strop, Koji Uehara and Wade Davis (2-0) combined for four scoreless innings, allowing two hits.
Chicago trailed 4-1 before Willson Contreras' RBI single in the sixth off Carlos Torres. Russell added a run-scoring bloop single in the eighth, poking the ball just over Eric Thames at first base.
Trying for his first four-out save this year, Feliz (0-2) struck out Javier Baez to strand a runner on third in the eighth. But Jon Jay walked with one out in the ninth, took third on a single by pinch-hitter Miguel Montero and scored on Kris Bryant's single.
Anthony Rizzo grounded out, and Russell followed with a drive into the left-field bleachers on a 2-0 count.
"You know when you go for a four-out save that something can happen in the ninth and to the Cubs' credit, they kept extending at-bats," Brewers manager Craig Counsell said. "That's the risk of doing it. But I'd do it again, because that at-bat in the eighth where he struck out Baez was big, too."
Travis Shaw and Jett Bandy homered off Hendricks, who finished third in the NL Cy Young Award voting last year.
Brewers starter Tommy Milone allowed one run and three hits in five innings on a cold afternoon at Wrigley Field, where the temperature dipped into the 40s. Rain delayed the start by 55 minutes.
"It was a tough day all around," Cubs manager Joe Maddon said. "But we just keep coming back for more.
"It is the resiliency, it is the fact that we do not quit. It's on the ring. We don't quit.' It's on the ring and there's a perfect example of it."
Chicago went 4-5 on its first homestand of the season.
Hendricks walked Milone in the fourth -- the first time in his four-year big league career that Hendricks walked a pitcher.
Two of Hendricks' walks were to Thames, who walked three times. Thames is one of baseball's hottest hitters, but did not get a hit for the first time in 13 starts this season.
Jon Lester was moved to Friday's game at Cincinnati by Maddon, who reset the rotation by flipping Lester with right-hander Jake Arrieta, who will pitch Saturday.
Barring rainouts or other changes, it means Lester will not pitch in Fenway Park against the Boston Red Sox, his former team, during next week's series.
Lester has not pitched at Fenway since July 20, 2014, and has not faced Boston since being traded to Oakland at the 2014 trade deadline.
Brewers: RHP Matt Garza (right groin strain) might be ready to pitch for Milwaukee after throwing 5 2/3 innings Monday during a rehab outing for Class A Wisconsin.
Cubs outfielder Kyle Schwarber, who missed most of last season with a knee injury, was out of the starting lineup for the first time this year. Schwarber struck out as a pinch hitter in the seventh inning and popped out in the ninth.
Brewers: RHP Zach Davies (0-2, 8.79 ERA) will open a four-game home set against St. Louis, which will start RHP Carlos Martinez (0-2, 3.57 ERA). The visit by the Cardinals kicks off a 10-game homestand.
Cubs: Following an off day, Lester (0-0, 1.00 ERA) starts against Cincinnati RHP Tim Adleman (0-0, 2.25 ERA).