Guess the experts were right. They said it was impossible to spell “Offensive Juggernaut” without using every letter in the word “Giants.” Isn’t that what everybody claimed?

No. That is not what anybody claimed. Not a single soul. The Giants were supposed to struggle offensively in the World Series, just as during the first two rounds of the playoffs, when they averaged barely three runs per game. So what has happened in the first two games?

Runs, runs and more runs. The Giants won Thursday’s Game 2 at AT&T Park by a score of 9-0 over the Texas Rangers. This came on the heels of an 11-7 victory in Game 1. The Series moves to Texas for the next three games. At this point, you’d have to make the Giants a three-touchdown favorite in Game 3.

What the heck is going on? Why has the Giants’ offensive drippy water tap suddenly turned into a firehose — while the Rangers’ vaunted offense has slowed to a trickle? Three reasons. And none involve plumbing or nuclear science.

The first reason is Texas’ pitching, especially from the bullpen. Of the 20 runs scored by the Giants in the first two games, 14 crossed the plate when the Rangers’ relief throwers were on the mound. They probably left Thursday’s game and wandered the streets of San Francisco, searching for the strike zone. In the eighth inning alone, they issued four consecutive walks, forcing home two runs.

“We benefited from the walks,” said Giants manager Bruce Bochy.

He has a future as a television analyst.

The second reason for the Giants’ offensive explosion is the approach being taken by their hitters. They are working the Rangers’ starting pitchers like crazy, fouling off balls or taking obvious pitches out of the strike zone as much as possible. This tires out the starters and gets the relievers into the game. And we know what happens with the Texas relievers. (See above.)

“We don’t normally score this much,” admitted outfielder Nate Schierholtz. “But it’s been nice watching it. Our guys have taken a lot of quality at-bats.”

And the third reason? That involves architecture. Specifically, it involves the dimensions and eccentric quirks of AT&T Park. In this postseason, the Giants now have a 5-2 record at their home ballpark.

Meanwhile, Texas has been firing popguns here ever since the place opened. Including the Rangers’ visits during interleague scheduling, they have now played 11 games at AT&T Park. Here is how many of those games they’ve won:

None. They are 0-for-11.

This tells you something. It tells you the Giants know how to play baseball in their park, while the Rangers have been totally clueless and flummoxed by the place. It showed up again and again during the first two games of the Series.

On streets outside the ballpark gates, banners hang from light poles that splash the team’s marketing campaign in bright letters: “There’s Magic Inside!”

No. It’s the deep outfield fences, including the vast space in right centerfield. It’s all driving the Rangers nuts. The park can get into your head.

“I have to think so,” Schierholtz said. “I think over the course of the season here, it gets into almost everyone’s head, even the guys here. Some of these balls they’re hitting into the gap for outs are going to be home runs somewhere else. When you square up the bat and hit the ball and it doesn’t go as far, it can really get frustrating.”

Ron Washington, the Texas manager, attributed much of the Rangers’ difficulties to the talented and “outstanding” Giants’ pitchers. But that’s also tied into the architecture. The pitchers throw the ball to induce as many balls as possible to be hit to the deepest parts of the park.

Matt Cain, who was Thursday’s starting pitcher, is particularly good at this. He gets more fly-ball outs than any other man on the Giants’ staff. It’s why Bochy prefers to start Cain in home playoff games.

That decision paid off again in Game 2, when Cain induced nine outfield fly-ball outs in his seven-plus innings of work. And it especially paid off in the fifth inning, when the game was still scoreless and up for grabs. The Rangers’ Ian Kinsler led off the inning by slamming the ball into deep centerfield. The hit looked like a homer for sure as it soared almost 400 feet toward the outfield wall, but then “…

Boink. Architecture struck again.

Kinsler’s ball actually hit right on top of the fence, bounced almost straight up and then kicked back toward the outfield, where the Giants’ Andres Torres caught it. He quickly threw the ball to second base, where Kinsler was pulling up for a mere double. The expression on Kinsler’s face was priceless. He looked like he had swallowed some of Brian Wilson’s beard dye.

“I wish it would have hit (the fence) and gone in the opposite direction,” Washington said. “But it didn’t. So we just had to live with it.”

“I thought it was a home run,” Cain said. “I thought it hit something behind the wall and bounced back, so I thought it was a home run. I cashed it in as one run. Then I saw that Torres had thrown it in and the runner was standing on second.”

Cain, leveraging the break, bore down and retired the Rangers, leaving them still scoreless instead of with a 1-0 lead. And eventually, the Giants broke through to win. Tellingly, in the Giants’ biggest hit of the game, Edgar Renteria sent a home run screaming down the left-field line and into a tunnel where homers love to go.

In nearly every World Series, the ballparks become important characters in the drama, from the howling noise of the Metrodome to the crowd-on-top-of-you feel of Fenway Park.

But right now, only one ballpark is leading the pack in intimidation. And it’s located at Third and King streets.

Contact Mark Purdy at mpurdy@mercurynews.com or 408-920-5092.