When roaming left, Bay's no wallflower

Jason Bay immediately solved Fenway Park's signature feature, the Wall that looms over him each time he takes his position in left field. He found the best way to play caroms, how to avoid the side wall that sneaks up on unsuspecting left fielders. But there are still a few things that make him uncertain.

"I'm still trying to figure out why that ladder is there," Bay said. "That baffles me."

Otherwise, Bay, in his first three months with the Red Sox, has mastered Fenway Park's unique left field. He has played 29 home games for the Sox, and his only error entering last night was a throwing miscue in mid-August. Not once has Bay been baffled by the curious bounces off the Wall or the oh-so-thin swatch of foul territory down the left-field line.

"Where I was coming from, there was a lot more room out there to roam," Bay said. "Now it's a lot less. It's pretty self-explanatory. If it's over your head, it's a home run. If it's off the Wall, back up. It's a little imposing at first. For the most part, I've enjoyed running less."

When the Red Sox traded for Bay at the July 31 deadline, he didn't panic about his new role as the man who plays in the Green Monster's shadow. He had played the Monster with the Pittsburgh Pirates and, while he knew it was different, he didn't have a problem.

"The way I look at it is, there's been at least a million guys that have played here before, and they got away unscathed," Bay said. "It wasn't really anything I was too worried about. I was just excited to stand out there."

When Bay arrived, he asked about the Wall's finer points. Third base coach DeMarlo Hale told him, "If it's over your head, back up far, it's gonna bounce high off the warning track. You can't cover everything."

Hale and Bay headed to left, and Hale drilled 20 fungoes off the Monster. Bay got used to playing balls off the wall from further away, familiarizing himself with the long caroms and potentially strange bounces.

Bay also needed to change his mind-set when throwing the ball back to the infield. Hale told Bay that on 99 percent of plays, the best throw would be to second base. Even if the ball eventually needed to be thrown home, the short throw to second would allow a timely relay.

"It's getting used to throwing to second almost every single time," Bay said. "And then you go on the road, you learn how to get your head back to doing it normal."

For Bay, adjusting to the lack of real estate along the left-field line presented a more difficult challenge. He never botched a play along the line, but it proved treacherous.

"There's the line, and there's about a foot, and then there's the wall," Bay said. "You want to get over there as fast as you can. You know if that ball falls, it's probably going to be a fair ball, which makes it even tougher, because you don't have a lot of room to catch the ball. And you don't have a lot of room to stop, because you don't know how close you are."

Part of Bay's success has been luck - he hasn't had to play a high fly ball that scrapes the Monster, which he said gave him the most trouble during his initial practice. "You want to get back to the Wall as fast as you can, but you also don't want to get up standing right on the warning track," Bay said. "It's very tough to judge whether it's going to hit the Wall or not."

Bay enjoys playing left field at Fenway, playing in the shadow of one of sports' most distinguished landmarks. He never notices the scoreboard at his back, but he saved a picture of himself standing in front of it.

"It's been really cool," he said. "I enjoy it. It's been pretty seamless so far. It's become a little friendlier than I originally thought, I'd say."

Adam Kilgore can be reached at akilgore@globe.com