CHICAGO -- Jake Arrieta continued his hot streak, striking out 11 and giving up three hits over eight innings in the Cubs' 8-2 victory over the Pirates on a chilly Saturday. Anthony Rizzo smacked a three-run homer as part of a four-RBI day and Addison Russell hit a two-run homer for the Cubs, who now have won Arrieta's last 21 starts, extending a franchise record.
"It's unusual," Cubs manager Joe Maddon said of Arrieta. "It's very unusual what he's doing."
All three Pittsburgh hits off the reigning National League Cy Young Award winner came in the fourth, including a two-run single by Francisco Cervelli. The Pirates have probably seen enough of Arrieta, who is 8-1 in 11 career starts against them.
"We know the run of success he's had, which is so well-deserved," Pirates starting pitcher Jeff Locke said. "He's pitched fantastic, as well as anybody in the world. Really, anybody in history."

With the win, Arrieta is 18-0 with a 0.75 ERA since Aug. 1 of last season, giving up 12 earned runs over 144 1/3 innings. He helped the Cubs improve to 27-8, their best start since the 1907 team opened with that record. Chicago now has outscored Pittsburgh, 37-11, in five games this season, and won each game by at least four runs.
"We've fared well against them this far, but we know the quality they have over there," Arrieta said of the Pirates. "We've just been playing some quality baseball. You just want to see your guys stay as hot as they can for as long as possible."
MOMENTS THAT MATTERED
Breaking through: After being unable to get a hit through three innings, the Pirates came through in the fourth to score two runs. Andrew McCutchen led off the inning with a double to left field before Gregory Polanco singled to move him to third. Polanco stole second and both runners later scored on a single by Cervelli. All three hits came on Arrieta sliders, and it was the first time Arrieta has given up more than one run in a start against the Pirates since September 2013.
Still, the Pirates lost the opportunity for more runs when a Josh Harrison ball hit off Arrieta's foot and bounced to Ben Zobrist for what became an inning-ending double play.

Fourth inning: Locke had given up one single over the first three innings, and the Cubs finally broke through in the fourth. Jason Heyward reached on an infield single and Kris Bryant walked to set up Rizzo's home run, his 11th of the season and second this year off a left-hander. Rizzo now has reached in a career-high 26 consecutive games, tops in the Majors.
"He's quietly having a pretty good year," Maddon said of Rizzo. "We talk about what Zobrist has been doing and [Bryant] and Russell, and here in the middle, you've got the rock. He's been spectacular."

Home sweet home: On Friday, Russell hit a go-ahead three-run homer against the Pirates, and on Saturday, he added a two-run shot. Before the game, Maddon was talking about how hard Russell was working in preparing for the afternoon game. It's paid off. He now has 13 RBIs in his last seven games.

"I felt I was a home run hitter," Russell said. "It's just tapping into that home run power, and it's just being a little more confident and barreling the ball and not being shy swinging the bat."
Looking for answers: Arrieta baffled Pirates hitters, as five of his 11 strikeouts were looking, including two on McCutchen. McCutchen did extend his hit streak to eight games, but with the exception of the fourth inning, the Pirates were again frustrated and couldn't get anything going on their way to a fifth loss in five games this season against the Cubs. Arrieta struck out seven of the final 11 batters he faced.
"A lot of strikes, a lot of shaving," Pirates manager Clint Hurdle said. "He threw a lot of strikes, a lot of quality strikes, especially the called third strikes. There were a lot of those, as well. He found a different rhythm and rhyme. I think he was using all four pitches, and the sequences, he was playing to what was going."
Said Cubs catcher Miguel Montero: "Those pitches, I call them, 'Hall of Fame pitches.' There's not much you can do with them."
SOUND SMART WITH YOUR FRIENDS
With Arrieta's outing, Cubs starting pitchers now have pitched through the fifth inning in the last 43 regular-season games, dating to Sept. 27 last season. That's the franchise's longest such streak since 1910.

Arrieta is the fifth pitcher in the modern era with at least 18 consecutive winning decisions in the regular season. He joins Carl Hubbell (24-0 in 1936-37), Roy Face (22-0 in 1958-59), Rube Marquard (20-0 in 1911-12) and Roger Clemens (20-0 in 1998-99).
EJECTIONS
Pirates pitching coach Ray Searage was ejected during his fourth-inning mound visit with Locke and Cervelli. Locke had walked Zobrist after Rizzo's home run, bringing Searage to the mound. Home-plate umpire Brian Knight walked out to end the visit, words were exchanged, and Searage was tossed.

"Obviously I can't share those words, but that's why we love Ray so much," Locke said. "He's got our back, just like we have his."
GOOD INTENTIONS
In the Chicago sixth, Knight issued a warning to both benches after Montero was hit by an 0-2 fastball from Locke. This came after Arrieta hit Jung Ho Kang in the fourth inning.

"[It was] 0-2, eight-hole, pitcher on deck, I pitch in as much as anybody in the big leagues does," Locke said. "Coming inside to him, I didn't want to miss over the plate. It's as simple as that. That's what [the umpire] sees. It's his job to maybe stop something before it happens if that were the case, but there was no intent with that pitch to hit anybody."
As for Arrieta's pitch to Kang, Locke speculated differently.
"I think any time someone like Arrieta hits somebody, you have to assume automatically that one didn't just get away," Locke said. "He's been pretty sharp all year … so when he misses like that, maybe you raise an eyebrow or something like that, too. … I don't know what happened on the pitch. It got him pretty flush, though. It just seems a guy like that, with pinpoint accuracy, doesn't just miss in. 
"But at the same time, you're not trying to throw cookies to anybody, either. … Not intentional, by any means, is what I'm saying, but it would have been more intentional-looking than the one I threw to Montero, for sure."
Told that the Pirates were upset about Arrieta hitting Kang, Montero defended his pitcher.
"He doesn't want to hit him, I guarantee that," Montero said of Arrieta. "He was a little wild that inning."
WHAT'S NEXT
Pirates: Right-hander Gerrit Cole starts for the Pirates in the finale of this three-game weekend series Sunday at 2:20 p.m. ET. Cole has struggled against the Cubs in his past two starts against them, but he is 5-1 in his career at Wrigley Field.
Cubs:Jon Lester will make his second start against the Pirates this season on Sunday in the series finale. On May 4 in Pittsburgh, Lester scattered eight hits over 5 2/3 scoreless innings. He's coming off a win over the Padres in which he picked up his first victory at home this season. First pitch will be 1:20 p.m. CT.
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