OAKLAND -- A concoction of shaving cream, water, and gatorade has never tasted so good. Just ask Derek Norris. Down to their final out, the A's rookie catcher hit his first career home run with a full count -- a three run walkoff shot that defeated the San Francisco Giants 4-2."It was surreal at first," Norris said. "Once I got punched in the back of the ribs a couple of times it kicked in. Then the pie in the face really set it in.""I didn't realize I got him as good as I did," a shaving cream pie-wielding Josh Reddick said. "Hopefully it comes as a good thing for him to get it in his face."At least Jonny Gomes and Brandon Inge had the decency to rinse him down with gatorade and water. They also greeted Norris with a round of applause when he entered the clubhouse. The A's win was a much needed twist of fate. Having already endured two tough losses at the hands of their cross-bay rivals, Oakland looked like it was staring in the face of a crushing sweep. Then Norris launched former Oakland pitcher Santiago Casilla's final offering into the left field bleachers.Ever wonder what a big-league manager is thinking in the bottom of the ninth inning, with two outs and his team down a run? "That if there is justice in the world he would hit the ball out of the ballpark," A's manager Bob Melvin admitted. "As soon as he hit it I knew it was gone." Melvin later clarified that his "justice" comment had nothing to do with the injustice that could have occurred in the sixth inning. With two runners aboard, Seth Smith appeared to have hit a double down the right field line. First base umpire Todd Tichenor ruled it a foul ball. Replays showed that the ball kicked up chalk from the foul line when it landed. The play would have scored at least one run for the A's. Instead, Smith ended up fouling out, stranding two runners.It appeared the A's had missed out on their chance to win the game. Apparently the baseball gods thought otherwise. Norris wasn't even supposed to be in the starting lineup. Kurt Suzuki was supposed to be catching Brandon McCarthy, who was scratched from his start. As a result, the A's called up A.J. Griffin to take the mound. Norris, who is familiar with Griffin since they played together in Triple-A, was asked to catch him. The rest is history. Griffin impressed in his Major League debut, throwing 104 pitches over six innings of work -- 71 one of them were strikes. He gave up three hits and allowed two earned runs. He had to oppose Giants ace Matt Cain. "You can't really let outside influences get to you too much," Griffin said. "You just go out there and pitch your game. I have no control over what Mr. Cain does."Griffin's only mistake came on a changeup in the first inning to Buster Posey, who deposited the ball into the left field seats for a two-run homer. After Posey's home run, Griffin only allowed two more baserunners. At one point he retired 13 Giants batters in a row. It is safe to say Griffin will be staying in the A's rotation for now. "Spectacular first outing," Melvin said. "If you can throw the ball where you want to and you have a secondary pitch you can pitch up here."The now have a little momentum as they embark on a seven game road trip. They will start in Seattle for three games and then play four games in Texas against the AL West-leading Rangers.