Cain, who had missed three games with an oblique strain, hit a solo homer leading off the eighth. Joc Pederson tied it with his first home run — and first hit — for the Cubs, a drive in the bottom half off reliever Devin Williams.
After automatic runner Daniel Robertson moved to third on a single by pinch-hitter Daniel Vogelbach in the 10th, Cain drove a 1-1 pitch from Brandon Workman (0-1) to the center-field batter’s eye on a warm afternoon at Wrigley Field.
“You're always happy to pull out a win, especially the way Woody pitched,” said Cain, who had his sixth career multihomer game and first since June 2017. “I'm still not where I want to be as far as my timing. I'm still trying to get back to my old form, but today was a good day.”
Cain, a two-time All-Star who turns 35 next week, played five games last season before opting out Aug. 1 because of coronavirus concerns.
Jason Heyward singled in automatic runner Kris Bryant in the Cubs 10th off J.P Feyereisen. After two walks loaded the bases, Brad Boxberger came on to retire Happ on a fly to short left for the final out and his first save.
Woodruff permitted just one hit, struck out eight and walked none in seven innings.
“He was just locked in with everything,” manager Craig Counsell said.
Woodruff was consistently ahead on counts and threw just 74 pitches. Still, he said he was starting to run out of steam when Counsell replaced him with Williams to start the eighth.
“I think that was the right move,” Woodruff said. "I was starting to lose myself in the delivery a little there.
“In the future, if I can get through seven (innings) on 74 pitches, they'll have to pretty much rip me off the mound," he said.
Josh Hader (2-0) pitched a scoreless ninth for the win.
Christian Yelich had three hits, including a double, and walked for Milwaukee.
The Cubs finished with only three hits after getting just one in a 4-0 loss to the Brewers on Tuesday night.
Pederson was happy to get one of the them and have it be big. He's now 1 for 17 after signing a one-year deal with Chicago.
“It was a big relief just to get on the board, and at a time to tie the game up and give ourselves a chance to win," Pederson said.
Cubs starter Kyle Hendricks nearly matched Woodruff through six scoreless innings. The Cubs ace allowed four hits, while walking none and fanning six.
Hendricks rebounded from a shaky opening-day start when he allowed three runs in three innings.
'It felt a lot better to be honest with you, kind of from the start, from the first pitch," he said. “Definitely on the right track.”
NOT QUITE NO-NOS
The Brewers became the first team with two no-hit bids of six-plus innings in the first six games of a season since the 1990 Padres. RHP Corbin Burnes didn’t allow a hit through the first six innings against Minnesota on Saturday, a game the Twins won 2-0 .
Brewers: 2B Kolten Wong was held out of the starting lineup with an oblique strain, but entered in the eighth as a defensive replacement. Robertson started at second in Wong’s place, then moved to third in the eighth.
Cubs: C Willson Contreras got a scheduled maintenance day off and Tony Wolters started behind the plate. Contreras pinch-hit and walked in the 10th. Contreras was hit by a pitch in the helmet on Monday and in the upper body in the ninth inning on Tuesday, but manager David Ross said the plunkings had nothing to do with resting the catcher.
Brewers: RHP Corbin Burnes (0-1, 1.42) takes the mound against St. Louis RHP Adam Wainwright (0-1, 20.25) in the Cardinals' home opener on Thursday afternoon.
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