"Just going for a pole," said Russell, who slammed a walk-off three-run homer with one out in the ninth to lift the Chicago Cubs to a 7-4 victory in a Wrigley Field series finale.
"I'm not trying to pull the ball, not trying to go the other way. I really want to get into it with my thoughts and get into it with my rhythm," he said.
It was the Cubs second walk-off win of the year and Russell's second career walk-off RBIs.
His heroics capped a four-run ninth that came on the heels of a single run in the eighth as the Cubs rallied from a 4-2 deficit.
"He's definitely not afraid ... and he still hasn't started hitting with any kind of consistency," said Cubs manager Joe Maddon. "Today was a classic example (in) the last two at-bats and staying with it mentally. He's just learning his craft, too."
The Cubs shortstop was 2-for-4 with four RBIs, including an eighth-inning single to shallow right to score Bryant and cut the deficit to a single run.
Chicago (8-7) won its second straight -- both comeback victories -- while Milwaukee (8-8) has lost two in a row.
Cubs reliever Wade Davis (2-0) pitched one inning to get the win, while Feliz (0-2) took the loss.
Travis Shaw and Jett Bandy each added home runs to Milwaukee's major league-leading total (29), but it wasn't enough as the Brewers couldn't hold a late-inning lead.
Neither Brewers left-handed starter Tommy Milone nor Cubs right-hander Kyle Hendricks figured in the decision.
Eric Thames walked and Shaw hit his fourth homer of the season -- and second in the series -- to give the Brewers a 2-0 lead in the first inning. Bandy made it 3-0 in the second with a lead-off solo home run to left, his fourth.
Cubs center fielder Albert Almora Jr. slugged his first homer of the season in the second, sending Milone's 3-and-1 pitch into the left field bleachers to cut the deficit to 3-1.
Milwaukee made it 4-1 in the fourth when Jonathan Villar singled home Orlando Arcia from second base with two out.
Hendricks worked five innings before being lifted for pinch-hitter Ben Zobrist. He allowed four runs on four hits, walked four and struck out four.
Cubs left-hander Mike Montgomery entered in relief, loaded the bases with one out but struck out Villar and got Thames to ground out to second after he fouled off four straight pitches.
Milone did not return for the sixth. He allowed one run on three hits and struck out five over five innings.
"He pitched very well today, it certainly as his best outing," said Brewers manager Craig Counsell. "I just thought he had his front-to-back stuff working, his change-up was very good. He did a nice job."
Corey Knebel, the Brewers' fourth pitcher of the day, got into a jam in the eighth with none out when he issued a lead-off walk to Bryant, gave up a base hit to Rizzo followed by a bloop hit to right by Russell that scored Bryant to make it a 4-3 game.
"They kept extending at-bats and fouling off pitches, to their credit," Counsell said. "Our guys kept throwing strikes and they foul off. When you make the pitcher throw eight, nine, 10 pitches in an at-bat, that makes it tough."
Bryant started the ninth inning rally when he forced a 4-4 tie with one out with a single to center that drove in Jon Jay off Neftali.
NOTES: The game was delayed 55 minutes when last morning rainfall drenched Chicago.
... Brewers RHP Zach Davies (0-2. 8.79 ERA) is Thursday's scheduled starter against Cardinals' RHP Carlos Martinez (0-2, 5.37 ERA) in a series opener at Miller Park. ... Milwaukee and Chicago are scheduled to meet again for a three-game Wrigley Field series from May 19-21. ... Tuesday's victory over the Brewers marked the first time since July 31, 2016, that the Cubs successfully rallied from five-runs down. ... RF Jason Heyward, the Cubs' top hitting regular (.300) had a day off from starting on Wednesday, as Matt Szczur got his first start of the season and batted leadoff. ... After 14 straight starts, LF Kyle Schwarber also got a rest. His .500 on-base percentage is third in the major leagues behind San Diego's Manuel Margot and Alex Gordon both .538. ... Cubs LHP Jon Lester (0-0, 1.00 ERA) is scheduled to go on Friday at Cincinnati against Reds RHP Tim Adleman (0-0, 2.25 ERA).