Posey catches on quick

One night last week, with his Giants in the middle of a gripping playoff race, Buster Posey came about as close as is humanly possible for a position player in the team sport of baseball to winning a game single-handedly.

From his catcher’s position, he blocked two balls in the dirt when the Chicago Cubs had runners on base, preventing those runners from advancing. He threw out a would-be base-stealer with a perfect throw to second.

From the cleanup spot in the lineup, he crushed a homer to straightaway center field in the eighth inning to break a scoreless tie. And as the field general behind the plate, he steered four Giants pitchers through an exquisite two-hit shutout in a 1-0 win at
Wrigley Field.

For all we know, he may have also written out the Giants’ lineup card, prepared the postgame spread and driven the team bus back to the hotel.

It was a game that encapsulated both the impact on the Giants of Posey, their preternaturally talented rookie catcher, and the exhilarating, maddening, tightrope-walking nature of the Giants themselves — who continue to hang tough in the teeming National League playoff race despite an offense known to vanish for weeks at a time.

For Posey, 23, the performance was the latest reason why he may be moving past Atlanta’s Jason Heyward and St. Louis’s Jaime Garcia in the race for National League Rookie of the Year.

Although Posey didn’t arrive in the big leagues until May 29, and didn’t take over the starting catching duties until July 1, he already has 16 home runs and 64 RBIs in only 382 at-bats. His .317 batting average, in fact, is just shy of the highest by a rookie catcher (minimum 50 games at the position) in history behind Mike Piazza’s .318 in 1993.

But the best argument for Posey is this: As the Giants, who open a three-game series against the Arizona Diamondbacks tonight at AT&T Park, battle the San Diego Padres and Colorado Rockies for the NL West title, and those two teams plus the Atlanta Braves for the wild card, he is their most indispensable player — the engine of their offense, the shepherd of their vaunted pitching staff.

And this: The Giants are 45-30 (entering Thursday) since July 1, the day after their trade of veteran Bengie Molina turned the starting catcher’s job over to Posey.

“Catchers have more responsibility than anybody on the field,” said Giants closer Brian Wilson, making the case for Posey. “We’re asking a 23-year-old rookie to take that leadership role. It doesn’t matter that he hasn’t been here the whole season.

The fact he can go out there, keep the game tempo, hit the way he has, know everybody on the pitching staff – to me it’s a no-brainer. The mound to home plate: That’s where the game is.”

But Posey’s one-man show Tuesday night also underscored some of the Giants’ acute shortcomings. Despite possessing the best starting rotation west of Philadelphia, the Giants are constantly playing 1-0 and 2-1 games — and losing their fair share — because they simply can’t score any runs.

In a span of 11 games from Sept. 10 through Wednesday, the Giants were involved in four 1-0 games, two 2-1 games and one 2-0 game — going a combined 3-4 in them. While their pitchers have put together a string of 16 consecutive games in which they have allowed three or fewer earned runs (entering Thursday) —- tied with the 1972 Indians and the 1981 Athletics for the longest such streaks since the start of the live ball era — they are only 10-6 in that span.

“Nothing is ever easy with us,” said veteran first baseman Aubrey Huff. “We’ve played a lot of close, low-scoring games. We’ve had to fight all year, in games where one or two runs wins it.”

It almost makes you wonder: Where might the Giants be if they had put Posey on their opening day roster (as the Braves did with Heyward), rather than leave him at Class AAA Fresno for nearly two months?

At the time that decision was made — toward the end of spring training — the Giants felt Posey’s bat was ready for the majors. But with a high-profile starting rotation headed by two-time defending NL Cy Young winner Tim Lincecum, the Giants (and perhaps the pitchers themselves) preferred the more experienced Molina behind the plate.

At Fresno, Posey found himself getting grilled in the dugout between innings by Grizzlies Manager Steve Decker, himself a former big league catcher, about situations, pitch-calling and game management.

“Just a lot of, ‘Why did you do this? Why didn’t you do that? How can you establish the fastball here? What’s the game plan with this hitter?’ “ recalled Decker. “It was all about getting an understanding of how to put the right fingers down.”

Asked whether he gained anything from his time in Fresno, Posey said, “It was definitely beneficial time. But could I have done the same thing with the Giants on opening day? I don’t know. I just tried to work to get better, no matter where I was.”

Mark DeRosa’s wrist injury led to Posey’s call-up to the majors on May 29, but initially he played almost exclusively at first base (with Huff shifting to the outfield), typically batting sixth or seventh.

But gradually, the Giants put more on his plate. On July 1, following the trade of Molina, Posey was told the catcher’s job was his. By the second week of July, he was their everyday cleanup hitter – to which he responded by batting .417/.466/.699 for the month of July.

“We were confident this kid was ready. It was his time,” said Manager Bruce Bochy. “When you come up, and you take over a pitching staff in the middle of a season, in a pennant race — it was something we wanted to work him into gradually. But because of his talent and his makeup, it made the transition easier.”

For a team to have put so much responsibility on a rookie is remarkable, and for that rookie to have responded as Posey has is even more so. The Giants, who haven’t made a postseason appearance since 2003, are hoping to become the first team to win a World Series with a rookie catcher since the 1946 St. Louis Cardinals did it with Joe Garagiola.

But for that to happen, Posey is going to need some help. He can’t do it all by himself, at least not every night.

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