MILWAUKEE -- Jordy Mercer's first career grand slam pushed the Pirates to the brink of something even rarer: A series win at Miller Park.
Mercer's slam off Matt Garza capped a five-run sixth that began with back-to-back errors by Brewers third baseman Jonathan Villar. Top Milwaukee prospect Orlando Arcia answered with a three-run shot in the bottom of the inning -- his first career home run -- but the Pirates held on, 5-3, for their second win in as many nights to open this four-game series.
"It's a pretty cool feeling, being the first one," Mercer said. "It's something you dream of as a little kid. Hitting a grand slam in the big leagues is pretty cool."
• In 0-2 hole, Mercer mashes timely first slam
The Pirates remained 2 1/2 games behind the Cardinals in the race for the second National League Wild Card. Pittsburgh entered this series on a nine-game Miller Park losing streak, but can win the series with a victory Saturday or Sunday.

Garza and Pirates starter Ryan Vogelsong dueled through five scoreless innings before the teams combined for eight runs against five pitchers in the sixth. With two runners aboard on Villar's errors, Starling Marte snapped the scoreless tie with a double three batters before Mercer fouled off consecutive two-strike pitches, then hit a slider just far enough to clear the fence for a 5-0 lead.
Garza's pitch was at the bottom of the strike zone, but it wasn't low enough.
"I've got to be better than that. I've got to be able to pick up my team when we need to be picked up," Garza said. "You know it was a big pitch, big situation. We walked a guy ahead of [Mercer] to get to who we wanted, and I floated a slider in there, and he front-footed it and hit a jetstream. It's one of those where it's going to [hurt] for a while."
MOMENTS THAT MATTERED
Expensive boots: All five Pirates runs in the sixth were unearned because of Villar's costly errors. He charged Andrew McCutchen's leadoff chopper, but said he took his eye off the ball in exchange for a glace at the speedy runner, and bobbled it for error No. 1. Gregory Polanco followed with a smash to the left side and Villar made a slick diving stop, only to air a throw over second base for error No. 2. Villar admitted he did a poor job of leading second baseman Scooter Gennett, who was playing the left-handed Polanco to pull, and had a fair distance to cover on his way to the bag. The plays left the Pirates with runners at the corners, nobody out and a big rally in the works.

"That's a tough one to swallow for [Garza] over there," Pirates manager Clint Hurdle said. "A couple errors in the inning to extend the inning, and then to hang a pitch and to get it hit out of the ballpark, that's hard. He competed very well tonight."
On the board in the bigs: Arcia has struggled in limited Major League duty, but enjoyed his best moment to date when he connected with reliever Jared Hughes' very first pitch, a slider, and sent it 408 feet (per Statcast™) to left field. The home run came in Arcia's 80th big league at-bat.

"I was looking for a pitch I could drive, a pitch I could hit hard," Arcia said through a translator. "[Catcher Martin] Maldonado had told me to look for the sinker, look for it up, because he'll leave it up a little bit. So I was just looking for one high, one I could drive, and I was able to get what I wanted." More >
Glovework: The Brewers had a chance to chip away in the eighth after speedster Keon Broxton worked a walk from Neftalí Feliz and stole second base -- his 13th in a row. Feliz held the line, striking out Arcia and retiring Maldonado on a fly out before getting help from Polanco to end the inning. Polanco charged a Hernán Pérez line drive and made a diving catch, preserving the Pirates' 5-3 advantage. The Brewers went 1-for-11 with runners in scoring position and left 11 men on base.
Video: PIT@MIL: Polanco takes hit away with diving grab
Not so elementary, Watson: Pirates closer Tony Watson came on to record his second consecutive save in the series and cruised through his first two hitters before running into trouble. Ryan Braun laced a two-out single up the middle and Chris Carter followed with a walk. A double steal put the tying run at second base, prompting a visit from pitching coach Ray Searage with a 2-0 count against Domingo Santana. On the next pitch, Watson got Santana to pop up to second baseman Josh Harrison to end the game. Watson has allowed five hits in 53 at-bats with runners in scoring position.

"He needed a break right there," Hurdle said. "The tying run went to second base, so just give him a break and help him hit the reset button. We just needed one good job."
Did Brewers manager Craig Counsell approve of Santana's aggressive 2-0 swing?
"Oh, yeah, for sure," he said. "We're a single away. You work your way into that count so you can be aggressive."

QUOTABLE
"The first time through the lineup was as good as I've seen since I've been in the dugout. He was really crisp, his off-speed stuff was outstanding. It was swing-and-miss stuff. The game boiled down to a couple of mistakes, a bad 0-2 pitch and that was the game. They took advantage of some of our mistakes." -- Counsell, on Garza

WHAT'S NEXT
Pirates: Pittsburgh goes for the series win Saturday at 7:10 p.m. ET at Miller Park. Rookie Jameson Taillon will make his 13rd start and third against the Brewers.
Brewers: Coming off a badly-needed win over the Rockies, Jimmy Nelson will try to make it two straight when he takes the mound Saturday at 6:10 p.m. CT. He's 5-2 with a 2.55 ERA in seven career starts against Pittsburgh.
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