The Cubs needed a win Wednesday night to avert a three-game sweep by division rival Milwaukee, and Murphy played a big role with three hits and a solo home run in Chicago's 6-4 victory against the Brewers.
Pedro Strop closed out a tense ninth inning as Chicago boosted its NL Central lead to four games over the second-place Brewers. Milwaukee is a half-game ahead of St. Louis for the top NL wild card.
Jose Quintana (12-9) gave up two runs in 6 2/3 innings, improving to 3-1 at Miller Park with the Cubs.
Strop allowed a walk and a single to open the ninth but got the final three outs, striking out Curtis Granderson with two runners on to preserve the win.
"It's a young group with a veteran mindset," said Murphy, who joined the Cubs in a trade with Washington on Aug. 21. "You lose a tough one (Monday) and they played really well yesterday. All you can do is come out and try to win this ballgame."
Granderson belted his first home run as a member of the Brewers in a pinch-hit role in the seventh, a two-run shot that cut Chicago's lead to 6-4.
After Travis Shaw walked and pinch-hitter Christian Yelich singled to start the ninth, the crowd of 37,427 was on its feet, nearly equally divided between Brewers and Cubs fans. Eric Thames flied out before Strop got Lorenzo Cain to ground to third for a force play. Then a nasty slider on a 2-2 pitch struck out Granderson.
"I thought he gained his composure nicely," Cubs manager Joe Maddon said of Strop. "He's got 95 or 96 (mph) with that sink. The slider he got Granderson on, it's good against righties and lefties."
Jhoulys Chacin (14-6) had tossed 16 consecutive scoreless innings against the Cubs this season before Murphy led off the fourth with an opposite-field homer into the Brewers' left-field bullpen.
"I was able to leverage the count in my favor and was able to look for something up in the zone," Murphy said. "I didn't think it was going to get out of the ballpark."
Javier Baez followed with a single and his aggressive baserunning helped the Cubs extend their lead. He raced for third on a single by Anthony Rizzo, and when Cain's throw from center field sailed, Baez scored and Rizzo went to third on a second error by shortstop Orlando Arcia. Ben Zobrist doubled to score Rizzo and give the Cubs a 3-0 lead.
A soft RBI single by Willson Contreras capped the four-run rally.
Jonathan Scoop's bad-hop single drove home a run in the bottom of the inning, and the Brewers loaded the bases with two outs. Quintana induced Arcia to hit a pop fly to shortstop to escape the jam.
Zobrist drove in his second run in the fifth with a two-out single, but Rizzo was thrown out at the plate trying to score from second base.
Kyle Schwarber belted his 25th homer into the second deck in right field in the sixth to make it 6-1.
"It was his best fastball of the year," Maddon said. "He primarily could have pitched with his fastball today -- it was that good."
The Brewers and Cubs will meet again in a three-game series at Wrigley Field next week.
"It was a fun series," Granderson said. "It's definitely something both teams can look at and say, all right, it's going to be a fight to the end."
A funny moment came in the fourth after Baez singled. He never moved off the base while Chacin threw over to first twice.
"They know I wanted to run," Baez said. "Right before Rizzo stepped to the plate, I saw the catcher (Erik Kratz) and he wasn't giving signs, so I knew (Chacin) was coming back (to first). Then after the first one, and he tried to act like he was giving signs. But I saw he was so fake about it, I just stayed there."
Baez scored moments later after Rizzo singled and Cain overthrew third base.
Cubs: Schwarber injured his back and left the game after homering in the sixth. "Before he went up to hit he told me it was tight," Maddon said. "But he may have taken his best swing of the year." . RHP Brandon Morrow may be reaching the point of no return for the Cubs, and Maddon said he will have to use several relievers in the closer role the rest of the season. Morrow, who posted 22 saves as the closer before being injured, has been sidelined since July 18 with right biceps inflammation. He has yet to throw off a mound in his rehab. "We'd love to have him back, but even if he does come back, how do you utilize that?" Maddon said. "You just can't push him two days in a row."
Brewers: Yelich was not in the starting lineup as the Brewers headed into the final stretch of the season. He singled as a pinch-hitter in the ninth to reach base in his 22nd straight game. "He needs a day off," manager Craig Counsell said before the game. "Friday was a thought, but it just reached a point where it had to be today." Yelich had not been out of the lineup since July 3.
Cubs: RHP Kyle Hendricks (11-10, 3.77 ERA) will open a four-game series in Washington on Thursday night.
Brewers: RHP Chase Anderson (9-7, 3.96 ERA) starts a three-game series against the Giants on Friday at Miller Park.
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