Plutko (2-0) struck out four and walked four in his second major league start. The right-hander was promoted from Triple-A Columbus to replace the struggling Josh Tomlin in Cleveland's rotation.
Michael Brantley, Francisco Lindor and Rajai Davis had two hits apiece as the AL Central leaders won for the third time in four games. Brantley extended his hitting streak to 12 games, and Davis also contributed a leaping catch against the wall in center, robbing Addison Russell of a likely run-scoring hit in the second.
The Indians completed a sweep of their two-game set versus the Cubs in their first appearance at Wrigley Field since they lost the 2016 World Series.
Chicago wasted a terrific start by Jon Lester (4-2) in its second straight loss after taking three of four last weekend in Cincinnati. The lefty allowed six hits, struck out four and walked one while lowering his ERA to 2.37 in his 10th start this year.
Plutko was even better. He retired 13 in a row before Anthony Rizzo led off the seventh with a double for Chicago's first hit. Willson Contreras then reached on an infield single, chasing Plutko and putting runners on the corners.
But Miller came in and shut the door, preserving Cleveland's 1-0 lead. He jumped on Javier Baez's bunt right back to him and threw out Rizzo at home. Russell then struck out swinging and Jason Heyward bounced to first, ending the inning.
Plutko also helped the Indians jump in front with a sacrifice in the third, advancing Davis to second after a leadoff single. It was Plutko's first professional plate appearance; he did not bat in the minors or during his college career at UCLA.
Lindor then popped out, but Brantley dumped an RBI single into center. The sweet-swinging Brantley also had two hits and scored twice in Tuesday's 10-1 victory over the Cubs.
Indians outfielder Brandon Guyer was placed on the 10-day disabled list with a neck strain after he got hurt in a collision with a fan. The injury occurred Saturday when Guyer went after a foul ball in Houston.
"When he went into the stands, he got like a forearm or something," manager Terry Francona said. "We checked him for concussions, but his neck is whiplash-ish kind of, so he hasn't played since that. I think he could've if he had to, but we're trying to be mindful of it."
Guyer is batting .150 with three homers and 10 RBI in 33 games. The move is retroactive to Sunday.
Indians: OF Bradley Zimmer (bruised left rib) hit in the cage, and Francona said he looked normal. "He's got a couple more days of this," Francona said. "Maybe sometime around Friday-ish, we'll see about what to do with him." ... OF Lonnie Chisenhall (right calf strain) went 0 for 1 and scored a run in his second rehab game with Triple-A Columbus.
Indians: RHP Mike Clevinger (3-1, 2.87 ERA) starts Thursday night as Cleveland begins a seven-game homestand with the first of four against Houston. RHP Charlie Morton (6-0, 1.94 ERA) pitches for the AL West-leading Astros.
Cubs: Following an off day, RHP Kyle Hendricks (3-3, 3.40 ERA) starts the opener of a three-game series against San Francisco. LHP Derek Holland (2-5, 4.94 ERA) pitches for the Giants on Friday afternoon.
Jay Cohen can be reached at https://twitter.com/jcohenap
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