CHICAGO -- Jake Arrieta wasn't perfect Friday afternoon, but he was characteristically stingy when it mattered most. Arrieta worked his way out of two key jams and struck out 11 over six scoreless innings as the Cubs beat the Pirates, 6-0, at Wrigley Field. The victory was Arrieta's 11th of the season -- tying him with crosstown ace Chris Sale for the Major League lead -- as he improved to 9-1 in his career vs. Pittsburgh.
"He's really good," Cubs manager Joe Maddon said. "His command still isn't what it can be. When it is, look out."
The Cubs bounced back quickly from just their fifth series loss of the season, jumping out to a 2-0 lead as Matt Szczur homered on Francisco Liriano's second pitch of the game. Chicago tacked on three more runs in the sixth after Arrieta left the game, beating Pittsburgh for the sixth time in seven meetings this season. Arrieta has a 1.46 ERA in 12 career starts against the Pirates.
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"I think it's fairly similar every time out," Arrieta said. "Execution is the most important aspect when you're facing a team multiple times, especially in a short time frame against a division rival who you see a lot. … I think when you face a team multiple times like that, you just have to minimize the amount of mistakes."
The Pirates, meanwhile, were shut out for the first time this season as they continued to slide further away from the division-leading Cubs. Though their bats were silenced by Arrieta and their offense continued to scuffle along, the Pirates' pitching remains their most glaring problem. Liriano walked five batters and couldn't get out of the sixth inning, and the Opening Day starter -- 1-6 with a 6.34 ERA over his last seven starts -- saw his ERA climb to 5.03. Pittsburgh has lost 15 of its last 20 games, falling below .500 for the first time since beginning the season 7-8.
"For a long time off the mound, it's looked easy for us because we've done so well," Pirates manager Clint Hurdle said. "It just goes to show you there is a large degree of difficulty up here. When you don't get consistency, it shows up."

MOMENTS THAT MATTERED
Master of escape: Arrieta walked the bases loaded with one out in the sixth. With his pitch count nearing its logical limit, Arrieta came back from 3-0 to strike out David Freese swinging. Then, with the Wrigley Field fans on their feet, he came back from 3-1 and struck out Matt Joyce looking to end the inning and preserve his scoreless outing. Arrieta also worked out of a jam in the third when Jordy Mercer and Chris Stewart started the inning with back-to-back singles. Arrieta struck out the side.
"[The sixth inning] is the game-changer," Maddon said. "Nearly every ballgame has a seminal moment, one that stands out. That obviously was it." More >

High-wire act: Liriano didn't allow a run between the first and sixth innings, but he flirted with disaster all day. The Cubs loaded the bases with two outs in the fourth, and Liriano got Szczur to ground out. A two-out walk to Addison Russell loaded the bases in the fifth, but Miguel Montero lined out to right. The trouble finally caught up to Liriano in the sixth. Pinch-hitter Chris Coghlan led off with a double, moved to third on a wild pitch and scored on Ben Zobrist's two-out single to center field. Liriano said he has struggled to find a rhythm on the mound, which has affected his delivery and the execution of his pitches.
"Trying to find a way to get in a rhythm, get better location with the fastball," Liriano said.

Hail, Szczur: Szczur's first-inning homer came on a first-pitch Liriano fastball that Szczur lasered into the left-field bleachers. The home run gave Arrieta an early lead to work with and also continued Szczur's excellent contribution off the bench this season. Szczur is hitting .333 and has driven in 15 runs in 60 at-bats.

Fanning the flame: Liriano left after 5 2/3 innings, and left-hander Cory Luebke entered with a man on first and two outs. But Luebke did more harm than good, walking three batters -- one of them intentionally and another to drive in a run -- without recording an out. Arquimedes Caminero, the Bucs' third pitcher of the inning, finally got them out of the sixth by retiring the first batter he faced.

QUOTABLE
"We're aware. We're working on things. We're trying to get better. We're not getting better as quickly as we need to."
--Hurdle, on the Pirates' high walk totals
SOUND SMART WITH YOUR FRIENDS
In his last 10 starts against the Pirates, including the National League Wild Card Game, Arrieta has allowed six earned runs -- and no homers -- in 72 innings.

The Cubs are 19-6 against NL Central opponents this season and 26-6 since Sept. 27. During that stretch, they've outscored their division rivals by a combined score of 189-78, good for a run differential of 111. Arrieta has done his part, going 11-0 with a 1.20 ERA in his last 13 starts against the NL Central.
STRANGE COLLISION
The Cubs scored their sixth run on a strange play in the seventh inning, one that resulted in Anthony Rizzo and Josh Harrison colliding and falling to the ground. With the bases loaded and two outs, Albert Almora Jr. grounded to shortstop Mercer, whose toss to second caused Harrison to reach over the bag. Rizzo was running from first and, as Harrison came across the base, Rizzo collided with him and both players tumbled to the dirt. Dexter Fowler scored from third on the play because Rizzo beat the throw to second but was tagged out after overrunning the base. The Pirates challenged, but the ruling was confirmed.
"It's a play that [coach] Dave McKay put in my head years ago," Rizzo said. "Two outs, if you can beat that throw to second, why slide? Run through the base, and if you're safe, the run scores."
Rizzo was hit by two pitches in the game, but Harrison said he didn't think the play was retaliation, understanding Rizzo's logic on running through the base. Harrison did take a tough hit on the play, but said postgame he was fine.
"Reminded me of football back in the day, getting a helmet in the hip flexor area," Harrison said. "After a couple minutes, I gained the feeling back. It just went dead for a minute, like a charley horse."

WHAT'S NEXT
Pirates: The Pirates will try to crack reigning NL Player of the Week Jon Lester on Saturday night at Wrigley Field, with first pitch at 8:15 p.m. ET. Pittsburgh will start left-hander Jonathon Niese, whose run of solid starts came to an end Sunday, when he allowed eight runs on 11 hits over 5 1/3 innings against the Cardinals.
Cubs: Lester will try to stay in prime form in Game 2 against the Pirates at 7:15 p.m. CT. Lester is 4-0 with a 0.59 ERA over his past four starts, and 3-3 with a 1.52 ERA in six career starts against the Pirates.
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