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8/23/2013 10:59 P.M. ET

Mercer gets look at third base against lefty

SAN FRANCISCO -- In an effort to match up best against Giants left-hander Madison Bumgarner, the Pirates broke out a new infield for Friday night's game.

Jordy Mercer made his first Major League start at third base, alongside the double-play combination of shortstop Clint Barmes and second baseman Neil Walker. It marked the first time those three infielders appeared in a starting lineup at the same time.

Mercer has seen considerable action at third base in the Minors, including 10 appearances there last season with Triple-A Indianapolis. But his big league time at the position was limited to one inning in a late-2012 game.

"I'll just try to have fun with it," Mercer said. "It's more about reaction time there. And you know that if you just knock a ball down, you have more time to make the throw, because it didn't take as long to get to you."

In the rare times when manager Clint Hurdle has given Pedro Alvarez a day off, the pinch third basemen had been Brandon Inge (no longer with the club), Josh Harrison (who started in right field Friday) and Russell Martin (who remained behind the plate to catch Charlie Morton ).

In Martin's two starts at third base, the Bucs had Michael McKenry to catch. Rookie Tony Sanchez is the only other receiver on the current roster.

"I felt we were best served leaving Russ where he is now," Hurdle said. "And I've seen Mercer do a lot of drill work at third, and during Spring Training. We felt comfortable moving him there."

Alvarez had faced Bumgarner only twice, and both at-bats resulted in strikeouts. At any rate, Hurdle was looking for the proper time to give him a timeout after he'd started 70 of the last 71 games.

"It's more about maintenance," Hurdle said of Alvarez's absence from the lineup. "He's been very active, on both sides of the ball, and he hasn't eased up on any of the pregame work."

With a two-run double in Thursday night's 10-5 victory, Alvarez matched his career high of 85 RBIs, first reached last season.

'Mission October' show has spotlight on Bucs

SAN FRANCISCO -- MLB Productions' stretch-drive series of up-close and all-access looks at postseason contenders -- "Mission October" -- is leading off with the Pirates. A crew is sticking close to the Bucs through the weekend, preparing for the show's Monday debut on Fox Sports 1.

Why lead off with the Pirates? Cynics out there will say that, given the team's history of falling out of the race the last two seasons, the producers had to act quick because they couldn't be sure Pittsburgh would qualify for future episodes.

Pirates manager Clint Hurdle had his own theory.

"When I was working for the MLB Network in 2009, I lost a bet to (on-site show producer) Jason Katz, so that's probably why he showed up here," Hurdle said.

Truthfully, MLB Productions jumped on the Pirates' bandwagon because they are a terrific, burgeoning story tugging at the heartstrings of underdog-loving America.

Hurdle and his players are trying to take it all in stride, and have ensured not being distracted by the attention.

"We've tried not to make big deal of it," the manager said. "A few more people around here. ... We've met the 'ask' professionally and responsibly. There was a lot of 'ask' and we said no to a lot, and yes to some."

First number, last word

2.81: The collective ERA of Pirates relievers entering Friday night's game against the Giants. That is the lowest mark for the Buccos' bullpen since 1975 when it finished the season with an ERA of 2.54.

"I could've very easily had the same first half as the second half I'm having. So it's not something I'm going to lose sleep over. I'll keep going out there with the plan of closing out inning after inning. Sometimes, I'm just giving hitters more credit than they deserve, not realizing that it's not that easy to hit a fastball down the middle." -- Jeff Locke, after lasting only four innings on Thursday night against the Giants.

Worth noting

• Recovering reliever Jason Grilli (right forearm tendon) is scheduled to throw another bullpen session on Sunday, then has been penciled in for a simulated game -- 25 pitches -- on Wednesday back in PNC Park.

• Entering Friday night's games, the only National League players who had reached base in more games than Andrew McCutchen's 105 were all Cincinnati Reds: Joey Votto (119), Shin-Soo Choo (110) and Jay Bruce (107).

• Clint Hurdle "was hoping" to get Starling Marte (bruised right hand), the league's leading hitter against left-handers, into Friday night's lineup against San Francisco southpaw Madison Bumgarner, but the left fielder "seems to be in a little bit of a holding pattern," the manager said.

Marte missed a fifth straight start since since being stepped on during a steal attempt Sunday, and the Pirates were considering placing him on the DL, after all, if he figured to miss the rest of the weekend.

Tom Singer is a reporter for MLB.com and writes an MLBlog Change for a Nickel. He can also be found on Twitter @Tom_Singer. This story was not subject to the approval of Major League Baseball or its clubs.