The moment was almost as unexpected as his entire season.

First, the instance from Wednesday night’s 9-8 Red Sox win over the Angels at Fenway Park.

“When I stepped in the batter's box,” Red Sox infielder Nick Green said, “I was like, ‘Oh (expletive)!' ”

The anxiety didn’t stem from the situation, which put Green up as a pinch-hitter with the bases loaded, two outs, and the Red Sox trailing by a run in the ninth inning. He didn’t mind that, having already felt the payoff of ending a game with a walk-off homer at Fenway earlier this season.

The problem was solely regarding his right leg.

Green had woken up with what he was diagnosing as “dead leg” Monday morning. He didn’t know what it was or how it became this way, but he did realize it was a problem.

Throughout the next few days Green managed to do just enough to execute batting practice, which was all anybody saw considering he hadn’t been called on to play in a game. He didn’t tell anybody about the issue, including Red Sox manager Terry Francona, figuring if the time came to spring into action he could figure out how to deal with it.

“I thought I was fine, but it was different once you get into the game,” he said. “You can get away with stuff in batting practice. It’s just different when you get in the game. … It doesn’t really hurt, just every time you put pressure on it, it collapses.”

It was a reality Green discovered with Angels reliever Brian Fuentes' first pitch, when the righty hitter swung and missed awkwardly. Then came pitch No. 2, and there was the same result.

“I didn’t feel right,” he said, “That’s for sure.”

Then came a check swing, which Angels manager Mike Scioscia thought was a game-ender, a notion not supported by first-base umpire Jeff Kellogg. On appeal, Kellogg said Green did not go around.

The hitter, who was subbing for first baseman Casey Kotchman, now had one ball. But with Green having to go to a knee on the check swing, the prospects of executing any kind of successful swing seemed remote.

“That’s why I said I was battling for my life,” he said. “I seriously did not think I could get a hit.” 

He managed to work the count to 3-and-2, forcing a do-or-die pitch from Fuentes, whom he had faced just twice before (with just a hit-by-pitch to show for it). Green’s success with the bases loaded throughout his career hadn’t been good — just four hits in 24 chances without a single walk.

And on none of those occasions was he dealing with the self-described diagnosis of “dead leg.”

Then came the final pitch of the at-bat, a fastball that everybody in an Angels uniform (along with NESN’s Amica Strike Zone feature) thought was a strike, coming in right around Green’s knees through the center of the plate.

Home plate ump Rick Reed viewed it differently. Green was going to play hero once again.

“What was the count in the end, 3-4 to Green?” Angels manager Mike Sciosca said.

“The 3-2 pitch. I had a problem with that,” Fuentes said. “It’s a big pitch, a huge pitch, and I’m buckling down and they’re buckling down. [The umpires] need to do the same. I’m a little frustrated right now emotionally, but I know in my heart of hearts that it wasn’t something against me, but for whatever reason they missed the call.”

Then came the next issue — actually getting to first base.

Green insinuated to the Red Sox dugout that he needed a pinch-runner, but with all of the moves already, Francona’s options were extremely limited. He would have to stay in the game, although not even having enough in the tank to execute any secondary leads leading up to Alex Gonzalez’ game-winning hit.

“I don’t know what it is. It feels like dead leg,’ Green said. “I almost collapsed every single swing, and almost collapsed walking down to first, and almost collapsed when I was leading off [first base]. I don’t know what’s wrong with it.”

By the time Green spoke with the media, he had already gone into the trainer’s room, iced the area of concern, and attempted to shake off the feeling that had lingered for the past three days.

In all, it was all a microcosm of Green’s season — somewhat gratifying but offering a big layer of frustration.

As the 31-year-old sits here, with just a few weeks to go before the end of the 2009 regular season, there is the feather in the cap that is being on the major league roster for the entire campaign, having played in the second-most games of his career (104).

“I never expected to be here all year,” said Green, who came to the Red Sox on a minor league contract. “That’s the last thing that crossed my mind, even at the beginning of the year.”

Then there are those other thoughts, which center around an August and September in which Green has played in just 25 games, a total he reached in one month back in June. And as his playing time diminishes, so has his batting average, which had been as high as .293 midway through June.

“I feel like I could have done so much better,” Green said just before heading back for more treatment. “Yeah, it’s a huge blessing that I’ve been here all year, but … I feel like I contributed a lot in the first half, but once the second half hit I didn’t do as well as I wanted to do. I try and forget about that stuff and think about the positives, but … I’m happy with being here all year, and I’m happy with helping the team when I have, I just feel like I could have done way better.

“If I look back at it, I do think I could have done so much better.”

Wednesday night, however, Green did plenty.