OAKLAND --No one can seem to explain it. The A's want to downplay it. Yet as the chatter around this team continues to develop into a deafening roar, the A's keep going out there and finding ways to achieve the improbable. It seems like the same story keeps repeating itself, and with each walk-off win you can tell that the A's players are starting to believe. You can see it in their eyes, you can hear it in their voices, and most obviously you can see it on the field. The most recent demonstration came on Sunday against the team with the best record in baseball. The A's battled back after being down 4-0, tied the game in the bottom of the ninth on a Seth Smith homer. Then Coco Crisp delivered the final blow, giving the A's their MLB-leading 11th walk-off win, a 5-4 victory in 12 innings that completed the franchise's first four-game sweep over the Yankees since 1972. "Everybody was up, everyone was excited, nobody got down," Crisp said. "We always feel we have a chance now.""It seems like every time we play at home we get a walk-off and everybody is waiting for it to happen," Kurt Suzuki said. The A's have two walk-off wins in their last three home games, and six in their last 11. The team has now won five-straight games and are seven games over .500 for the first time since 2008. Predictably, the most recent walk-off hero was rewarded in the customary fashion."You know it's coming, if you dodge it you are going to get something in the clubhouse now," Crisp said of the light and fluffy cream based punishment. "You've got stuff in your nose, sunflower seeds in my nest of hair but that's all part of the enjoyment of a victory like this."If you thought the A's celebration on the field was wild, it wasn't over. They started hollering and cheering again when they saw a highlight of their final hit on the TV in the clubhouse too. "It's exciting," Smith said. "You've got pitchers that will keep you in the game to the end, you've got a bunch of grinders that aren't going to give away any at-bats and are going to try and get the job done every time."It sure seems like a simple recipe for success when it's explained that way. It's much more complicated than that though as it plays out on the field. Starting pitcher Bartolo Colon got into trouble allowing three runs in the third inning and a fourth run in the fourth frame on Curtis Granderson's 26th home run of the season. The veteran pitcher retired the next eight batters he faced and managed to pitch his way into the seventh inning. "A lot of good things happened today," A's manager Bob Melvin said. "It started out looking like it was going to be 12 to nothing and Bartolo really deflected some blows." The A's 11 walk-off wins have had 10 different heroes. The A's are using every last player to scrape out these wins. On this day All-Star closer Ryan Cook and rookie Sean Doolittle weren't available out the bullpen. Yet over 5.1 innings the bullpen didn't allow a single run.Suzuki even got in on the act, clubbing his first home run in 78 games. Naturally the team completely ignored him when he got back to the dugout before swarming him in celebration. Just another way the A's are keeping it loose. "I knew it. I didn't care obviously," Suzuki said of the silent treatment. "It's definitely good to get that first home run out of the way."Brandon Inge also hit his second homer in as many days. With his 10th homer he became the sixth player on the A's to reach double-digits in home runs. The A's just completed a six-game home stand against the Rangers and Yankees -- the top two teams, record-wise, in baseball. They ended up winning five games. It's safe to say nobody saw that coming. "To go 5-1 was pretty remarkable," Melvin said. "Beating these guys four games in a row as well as they've been playing coming in here is pretty remarkable.""Probably a little bit unexpected," he admitted.The A's are now tied for the top Wild Card spot in the American League. They embark on a nine-game road trip that will take them to Toronto, Baltimore, and Tampa Bay. On the road they'll have to find a way to win without their trademark walk-off style.