Here’s the story — or at least as much of the story as we were able to glean after the game — on the missed suicide squeeze by Juan Pierre in the second inning, the one that resulted in Andre Ethier getting caught in a rundown between third and home. OK, first of all, Pierre admitted that he missed the sign. His half-bunt, half-swing at the pitch appeared to be a panic move when he saw Ethier barreling down the line. But here’s the rub: because the suicide is such a high-risk, low-percentage play — Grady says there is one thing that can go right and 10 things that can go wrong — teams generally employ a sign system that involves not only the sign being given to the runner and the batter, but the sign being acknowledged by all parties so everyone knows they have the signs. 3B coach Rich Donnelly was understandably vague after the game, because obviously you can’t tell reporters how your sign system works. But Donnelly DID say the acknowledgement mechanism is something that happens BEFORE the sign is given. (I’m guessing that would make a lot more sense if we knew what the signs were, but we never will, so just go along with it). Grady implied that Pierre had acknowledged the sign. But Pierre said he wasn’t aware of any such acknowledgement mechanism. At any rate, the play would loom large on a night when the Dodgers left five runners in scoring position and lost by a run. They fell to 13-9, and the Giants, by winning their eighth game in a row, pulled even with the Dodgers atop the NL West. Dodgers begin a three-gamer tonight at Petco, where the Padres are just a game back. … For the fifth game in a row, the Dodgers went to the bottom of the ninth trailing. For the third game in a row, they DIDN’T play We’re Not Going to Take It by Twisted Sister. … Grady said there won’t be MAJOR changes to the lineup tomorrow night. But the key word is MAJOR. Stay tuned.