It’s been a gray, gloomy morning at AT&T Park, marked with periods of light rain about an hour before first pitch. The future looks similarly bleak, considering the news on Pablo Sandoval that we all knew was coming since about 11 pm Wednesday night. Sandoval broke the hamate bone in his left hand, almost a year to the day that he suffered the same injury to his right hand. Sandoval will undergo surgery on Friday, and is scheduled to miss four-to-six weeks. Again.

It appeared that Sandoval injured his left hand on Wednesday night, but that wasn’t the case. He was able to successfully push through the injury for a short time, but last night forced an MRI and you know the rest.

“He thinks he did it Sunday. They really don’t know when he did it,” Bruce Bochy said.

“After the day off Monday he came in Tuesday, some soreness. He had a nice game, with a home run and the double. He hit a home run Sunday. Just got to the point where you have to do something.

“It took the whole four-to-six weeks last time. Hoping that’s not the case this time.”

Giants trainer Dave Groeschner was cautiously optimistic, saying it was better that the injury occurred to Sandoval’s left hand this time, since he throws right handed and hits lefty more often. According to Groeschner, the bottom hand causes more trouble with an injury to one’s hambone.

But the Giants and their fans aren’t used to quick recoveries from their hitters (cough … Freddy … cough), and another month or so without Sandoval makes one wonder how the Giants will score any runs at all. They’ve only scored 5 or more runs three times in the past 17 games with the Panda playing every inning — besides the last four frames on Wednesday night.

Still, the Giants will try to get this rainy day game in and send the Miami Marlins out of town with one defeat. The season must go on, and it’s up to Bochy and the players left over to keep the team from sinking too far below all the non-Padres squads in the NL West.

Conor Gillaspie is starting today. He hits second and plays third, and the Giants hope his Fresno numbers (.362/.417/.521) carry over to the point where they feel comfortable making him Sandoval’s full-time replacement.

“Right now I’m hoping Conor takes it and runs with it. He was our third baseman in Triple-A, and he’s played there longer than everybody. And with the bat, he’s been swinging it well. So I’d say he’s going to get most of the playing time,” Bochy said. “The other options are Arias, Theriot, even Burriss.”

What about Brett Pill, who the Giants seemed to be hoping they could mold into a third baseman during Spring Training? Remember the Scott Rolen comparisons?

“Pill? Nah, not an everyday option. He just hasn’t played that much there,” said Bochy. “He’s probably going to get some time there, but not on an everyday basis.”

Bochy, hoping for offensive energy that has been mostly sapped/nonexistent over the past 13 months, said what all managers say after injuries. But at this point, he’s almost pleading for his guys to start hitting and make his job easier.

“Hopefully some of these guys will look at this as a great chance for them to show what they can do and go out and shine,” He said.

“You just don’t replace a bat like Pablo. This guy was on the All-Star team last year. There’s few guys in Major League Baseball that can do some things he can do with the bat.”

If Gillaspie’s the only third baseman Bochy trusts, who’s the next hitter on the chopping block? They’re going to have to figure this out soon, because…

“We hope Huff is available to come back on Monday, which would be a shot in the arm for us,” Bochy said of his anxiety-stricken 1B/OF, who hit a few homers onto the arcade during BP this morning. So who would Huff replace? Gillaspie is yet another left-handed hitter, so would they really part with Pill? Brandon Belt isn’t hitting for power, but he’s getting on base at a decent clip. Emannuel Burriss seems to have fallen out of favor, but would they DFA him at this point, with so little middle infield depth already?

This looks like a battle between Joaquin Arias and Brandon Crawford. Crawford leads the team in doubles with 7, but his defense hasn’t been as clean as many would like and his OBP is .234. Arias is fighting an uphill battle since he didn’t make the team out of Spring Training, but he hit in Fresno, he’s hit so far here (extremely small sample size, but that doesn’t always matter on this team) and he made a pretty amazing play at shortstop in the 10th inning last night.

The focus while constructing this lineup has been almost entirely on offense, so whoever hits between now and Monday may be the ones who save their jobs.