We already told you about Buster Posey's walk-off homer from Wednesday night , as the San Francisco Giants sunk the Colorado Rockies. But do you know who told you about it before it even happened? MLB Network's Greg Amsinger , who predicted Posey would hit a walk-off during a live look-in on "MLB Tonight." Amsinger even mimicked Giants announcer Duane Kuiper's "It. Is. Outta Herrrrrrre" home-run call seconds before Posey's ninth-inning blast. Even better than predicting the homer, though, was Amsinger's reaction when the ball left the yard. At that point, MLB Network had gone live to the Giants broadcasters, so Aminger's told-you-so celebration happened off air. But MLB Network cameras captured it and we think it's worth your attention: We feel compelled to remind you that Amsinger also told Mike Trout before the All-Star Game that he would triple in Derek Jeter, and that's exactly what happened . Mr. Amsinger, I'd appreciated it if you did me a solid and predicted "Mike Oz is going to win the Mega Millions." Thanks, pal. More MLB coverage from Yahoo Sports: - - - - - - - Mike Oz is an editor for Big League Stew on Yahoo Sports. Have a tip? Email him at mikeozstew@yahoo.com or...