CHICAGO -- Saturday was the 20th career start for Madison Bumgarner against former Cy Young Award winners. He was winless in four such outings this season, but ended that streak at Wrigley Field, as the lefty and his Giants topped the Cubs and Jake Arrieta.
Bumgarner struck out 10 over six innings in the Giants' 3-2 victory over the Cubs in front of a crowd of 41,250. Arrieta, the reigning National League Cy Young winner, lost for the first time since July 30. The defeat also ended Chicago's five-game winning streak.
"You know coming in, it's going to be a close game -- probably a one-run ballgame -- and we just got outplayed today," Arrieta said. "They made a few more plays than we did. That was really the turning point in the game."
This game wasn't just about pitching, as Brandon Crawford and Javier Báez showed off their baserunning skills. Crawford singled, stole second, then swiped third before he came home on a wild pitch by Arrieta in the Giants' sixth. Baez dashed home from second on an infield hit by Arrieta in the fifth.
This series could be a preview of the National League Division Series. The Cubs and Giants entered the All-Star break with the top two records in the Majors, but have gone in different directions since then. The Giants lead the NL Wild Card, but are an MLB-worst 16-29 since the break, while the NL Central-leading Cubs are an MLB best 34-13 despite the loss.
"It could be [a preview]," Arrieta said. "We're a really good team, I like us against anybody."
Accenting the intensity of this matchup, each game in this series has been a one-run decision. "Every little thing has mattered in these three games," Giants second baseman Joe Panik said.
MOMENTS THAT MATTERED
Bumgarner's best: San Francisco's ace blanked Chicago on one hit through four innings, before the Cubs scratched across runs in the fifth and sixth. Bumgarner (14-8) nevertheless improved to 8-2 with a 2.25 ERA in 12 career starts against Chicago.
"He commanded the ball well and did a good job of keeping the ball out of the middle of the plate, for the most part," Giants catcher Buster Posey said of Bumgarner, who walked none in his first road victory since June 30 at Oakland.
Of his matchup against Arrieta, Bumgarner said, "You're not really pitching against him. ... You're pitching against the Cubs' lineup."
On your mark:Willson Contreras doubled to open the second, and that was the Cubs' only hit off Bumgarner until the fifth, when Baez singled to lead off. Baez then stole second when Matt Szczur struck out. Arrieta chopped an infield single that third baseman Eduardo Núñez overran, and Baez hustled home to cut the score to, 2-1. Bumgarner struck out pinch-hitter Jorge Soler and Dexter Fowler to end the inning.
"We were aggressive on the bases, and that's what we preach and what we do -- and we're going to look bad doing it sometimes and we're going to look really good, and that play Javy made was incredible," said Anthony Rizzo, who was doubled off second in the ninth inning after making an aggressive turn.

Base-ic instinct: Brandon Crawford manufactured a sixth-inning run with shrewd baserunning. He singled off Arrieta, stole second base, then proceeded to pilfer third, when he realized that he could beat Baez to the bag in the event of a throw. Reaching third proved essential for Crawford and the Giants, as a wild pitch enabled him to score.

"The one [play] you'd like to get back was Crawford going to third base unencumbered," Cubs manager Joe Maddon said. More >
Missed opportunities: The Cubs loaded the bases in the sixth against Bumgarner, but he gave up a sacrifice fly to Baez and then escaped by striking out Szczur. Chicago loaded the bases again in the seventh, but Hunter Strickland got Addison Russell to fly out to right to end that threat. The Cubs were 2-for-8 with runners in scoring position and stranded nine.

SOUND SMART WITH YOUR FRIENDS
First baseman Brandon Belt dropped a first-inning popup, ending the Giants' franchise-record streak of consecutive errorless games at 17. It wasn't a routine play for Belt, who had to cope with the sun and the tricky wind as he converged around the pitcher's mound along with other infielders for the ball.

REPLAY REVIEW
Baez dove head first into first base in the Cubs' eighth, and was called safe. But the Giants challenged the ruling, saying Belt had flipped to Sergio Romo, who stepped on the bag in time. After a review, the call was overturned and Baez was out.

WHAT'S NEXT
Giants:Johnny Cueto will make his 15th career start at Wrigley Field in Sunday's 11:20 a.m. PT series finale. The right-hander is 5-5 with a 3.22 ERA lifetime at the Friendly Confines. Cueto also is 8-2 with a 3.08 ERA in 14 road starts this season.
Cubs:John Lackey returns from the disabled list to make his first start since Aug. 14. Lackey had been sidelined with a right shoulder strain. He has thrown five straight quality starts, going 2-1 with a 2.14 ERA in that stretch. Lackey also has done well at Wrigley Field, where he has a 2.47 ERA in 13 starts. First pitch is scheduled for 1:20 p.m. CT.
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