PITTSBURGH -- Backed by the Giants' biggest offensive performance of the year, Johnny Cueto continued his dominant stretch against an opponent that's too often seen him at his best. San Francisco tallied a season-high 22 hits, Cueto fired 6 2/3 strong innings and the Giants beat the Pirates, 15-4, on Tuesday night at PNC Park.
A night after being shut out by Jeff Locke and three Pirates relievers, the Giants gave Cueto plenty of breathing room. San Francisco broke out against Pittsburgh spot starter Wilfredo Boscan in the fourth, putting up seven runs and batting around before recording an out. Angel Pagan delivered the biggest hit, a first-pitch grand slam to center field, and Conor Gillaspie followed with a two-run homer deep into the right-field seats.
"When you get seven scored on you in one inning, it changes the direction of the game immediately," Pirates manager Clint Hurdle said. "We've had some challenges along these lines. ... We didn't do enough things well to win the game. Matter of fact, we got beat pretty good tonight."

The Giants' 15 runs were the most allowed by the Pirates this season and the most ever scored by San Francisco at PNC Park. The Pirates, meanwhile, have allowed double-digit runs in four of their last 12 games -- but Tuesday night was an unfortunate high mark for the struggling Bucs, who had to send backup catcher Erik Kratz to the mound in the ninth inning. Naturally, Kratz put up the Pirates' first scoreless frame since the third inning.
• Kratz pitches in with mound appearance
"We're just trying to patch games up when we get underneath like this," Hurdle said. "Unfortunately, we've had a few that we've had to deal with. ... You do the best you can with what you've got and where you are."
Cueto limited the Pirates to one run on four hits while striking out six, picking up his 11th win and cruising to a career-high eight-game winning streak. In nine starts since May 7, Cueto has put together a 1.07 ERA. Changing uniforms has done nothing to cease his mastery of the Pirates, as he improved to 19-4 with a 2.10 ERA in 29 career starts against Pittsburgh.

"I didn't know the number," Cueto said through his interpreter, Erwin Higueros. "But after I lost the Wild Card game against them [in 2013], I told myself I need to concentrate and try to win as many as I can."
Cueto's effort and a breakout night for San Francisco's lineup put the Giants back in the win column, giving them 28 victories over their last 37 games. Pittsburgh has lost 18 of its last 24 games.
MOMENTS THAT MATTERED
Anatomy of a big inning: Pagan's grand slam and Gillaspie's homer obviously were the biggest hits in the Giants' fourth-inning outburst. But the key to the inning might have been Brandon Crawford's 11-pitch bases-loaded walk, which immediately preceded Pagan's first-pitch clout.

"I think Crawford's walk was the game-changer," Giants manager Bruce Bochy said. "I'm pretty sure that it took something out of [Boscan]."
No. 1 for No. 58: Positive moments were few and far between for the Pirates, but catcher Jacob Stallings notched a memorable accomplishment in the seventh inning, recording his first Major League hit and RBI -- a double to left field off Cueto that put the Bucs on the board. Stallings was called up to make his Major League debut Sunday, and with catcher Chris Stewart apparently healthy enough to play -- he pinch-hit in the eighth inning -- Stallings may be heading back to Triple-A soon.

"When I saw who we were facing the first three games of the series -- Bumgarner, Cueto and Samardzija -- I was like, 'Well, all right. This is going to be a little hard to get my first one,'" said Stallings, whose family and college coaches were in attendance. "It was pretty special. It was fun. ... Bittersweet, just because of the outcome of the game."
Encouraging "debut": In his first start at third base since Matt Duffy, the regular at that spot, went on the disabled list Monday, Gillaspie went 4-for-5, lifting his batting average from .159 to .224, and drove in four runs. Gillaspie's in position to give the Giants a major boost, since he's expected to be the club's primary third baseman until Duffy recovers from his strained left Achilles.

"Obviously, with Duffy going down for a couple of weeks, I'm happy to step in and try to do the best I can," Gillaspie said.
Said Bochy of Gillaspie's effort, "It should give him a lot of confidence."
Bad to worse: Already facing a huge deficit and playing with key players Gerrit Cole and Francisco Cervelli on the disabled list, the Pirates lost Starling Marte to left foot discomfort in the eighth inning. After trying to run down Ramiro Pena's triple to the center-field wall, Marte came up limping, grabbed at his lower left leg and left the game shortly afterward with assistant athletic trainer Ben Potenziano and Hurdle.

QUOTABLE
"There's nothing really scientific about it or anything. I'm just trying to throw strikes and not blow my arm out." -- Kratz
"I threw a changeup in my outing in Seattle, and it went to the backstop. May have too much torque on that pitch. I'm not sure what my spin rate is on it. I canned that pitch in my last outing." -- Kratz, on his fastball-knuckleball arsenal

SOUND SMART WITH YOUR FRIENDS
Cueto became the first Giants pitcher to record 11 wins in his first 15 starts since Rick Reuschel did so in 1989. San Francisco has gone 13-2 in his starts this season.
The Giants had seven doubles, one shy of matching their single-game San Francisco-era record. They had eight doubles May 29 in Colorado and matched that total three times in 2000.

Outfielder Jaff Decker, now with the Rays, was the last Pirates position player to pitch in a game, doing so last July 30. The last position player to pitch against the Giants? Steve Finley for the D-backs on Aug. 30, 2001.
UPON FURTHER REVIEW
The Giants challenged a sixth-inning call that ruled Brandon Belt's two-out, opposite-field line drive to left landed foul. After a replay review, the call was overturned and Belt was awarded a double.

In the seventh inning, the Pirates challenged a call ruling Gillaspie safe at second base. Upon review, it was ruled second baseman Josh Harrison had tagged Gillaspie before throwing to first baseman John Jaso, and the Pirates were awarded a double play.

The Pirates challenged what would have been the last out of the game, Gregory Polanco's grounder to shortstop. Polanco was initially called out, but the ruling was overturned. He came around to score on David Freese's double to center field.

WHAT'S NEXT
Giants: Right-hander Jeff Samardzija, who snapped a two-game losing streak last Friday against the Rays by pitching a complete game, will be in comfortable environs when he opposes the Pirates on Wednesday. Samardzija owns a 1.26 lifetime ERA at PNC Park, where he has limited opponents to a .167 batting average. Overall, he has a 2.25 ERA against the Pirates.
Pirates: Left-hander Francisco Liriano will try again to turn around his season when he takes the mound at PNC Park on Wednesday night. Liriano, Pittsburgh's Opening Day starter, fell to 4-7 with a 5.03 ERA after giving up four runs on six hits and five walks against the Cubs on Friday.
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