Three homers back Arrieta to 16th victory

SAN FRANCISCO -- Jake Arrieta could be looking ahead and counting how many games he might win this season, but the Cubs right-hander is focused on posting a quality start, and it's paid off.

Arrieta became the first pitcher in the Major Leagues to reach 16 wins and Kyle Schwarber, Miguel Montero and Starlin Castro each homered to power the Cubs to an 8-5 victory over the Giants on Tuesday night. Chicago now has won 21 of its last 25 games.

With the win, the Cubs pulled within two games of the Pirates in the National League Wild Card standings and also matched their win total of last season (73). Arrieta gave up four singles and struck out eight over six-plus innings for his 13th consecutive quality start. He has a 1.17 ERA in those 13 games.

"They've got a balanced lineup and one that requires some work," Arrieta said of the Giants. "You really want to bear down and make them hit your pitch."

San Francisco's Matt Cain took the loss and was charged with six runs over five innings, the seventh time in 10 outings in which he's given up at least four runs. The Giants dropped 7 1/2 games back in the Wild Card race and lost for the sixth time in their last eight games.

"That's the only way to do it is to keep pitching and keep throwing," Cain said of trying to get on track. "I've got to build off bullpens in between and the little things. You can't get stuck on what the result is."

MOMENTS THAT MATTERED
Kaboom: Schwarber launched his home run with two on and two outs in the third and now has four hits over his last eight games, and all have been homers. According to Elias, he is the first Cubs player since 1900 to hit 12 homers in his first 42 career games. Montero hit a two-run homer in the fourth and Castro had three hits, including a solo shot in the sixth, to raise the Cubs' home run total since the All-Star break to 55, tops in the National League.

Video: CHC@SF: Montero makes it 5-0 with a two-run shot

What's the cause of the power surge?

"Confidence -- just confidence," Cubs manager Joe Maddon said.

Free pass proves costly: Citing one flaw in Cain's performance borders on nitpicking, considering 10 Cubs reached base safely against him. But he might have prevented Chicago's trio of third-inning runs had he avoided walking No. 9 hitter Tommy La Stella on four pitches with one out and Castro on third base. Schwarber homered two batters later.

Video: CHC@SF: Schwarber cranks a three-run shot off Cain

"It just looked like his [arm] slot changed a little bit; it got a little lower, and pitches flattened out," Giants manager Bruce Bochy said.

Arms race: If there was one glitch in the game, it was that Maddon had to use Pedro Strop and Hector Rondon in the eighth and ninth innings, respectively, when the plan was to give both right-handers a day off. With Jason Motte on the disabled list, Maddon wanted Tommy Hunter and Clayton Richard to fill the void. Hunter gave up three runs on two hits and a walk, and Richard failed to retire either batter he faced.

"That's when we have to really batten down the hatches," Maddon said of his 'pen. "[We need] to make sure that when certain guys can have a day off, they can get the day off."

Susac leads surge: Andrew Susac's bases-loaded double off Richard accounted for three runs in San Francisco's four-run, eighth-inning rally that made the score less lopsided. Gregor Blanco preceded Susac's big hit with an RBI single.

Video: CHC@SF: Susac clears the bases with a double

QUOTABLE
"What I can appreciate is how well these guys are acclimating themselves to this kind of competition so quickly. That's the most exciting part for me about our team, is how they're able to make adjustments so quickly and be successful on a ballclub that is however many games over .500 and playing extremely well and being a huge part of what we're doing here. I don't think they put much thought into it, which is exactly the way they should be approaching it. Having that mindset allows them to come here and not necessarily feel pressure but come out here and play." -- Arrieta on the young Cubs in the lineup.

SOUND SMART WITH YOUR FRIENDS
Arrieta is the first Cubs pitcher with 13 straight quality starts since Greg Maddux had 14 in a row in 1992, when he won the first of his four Cy Young awards.

WHAT'S NEXT
Cubs: Kyle Hendricks will start Wednesday's second game of the three-game series, and second this season against the Giants. He picked up the win Aug. 8 at Wrigley Field, giving up three runs over 5 1/3 innings. First pitch is scheduled for 9:15 p.m. CT.

Giants: Jake Peavy, who will oppose Chicago in Wednesday's 7:15 p.m. PT rematch, will try to avoid the arduous type of first inning that he endured Aug. 9 at Wrigley Field, where he threw 38 first-inning pitches and tired himself prematurely in a 2-0 loss.

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