Baltimore Orioles third baseman Manny Machado led off the 12th inning with a walk-off home run over the left-field wall for his 11th homer this season. (Kevin Richardson/Baltimore Sun video)

He’s only 22, but Orioles third baseman Manny Machado said his memory’s a little fuzzy. He doesn’t think he has ever hit a walk-off home run before, not as an amateur and probably not as a minor leaguer.

He knows for sure he had never hit one in the major leagues until the 12th inning Tuesday night, when he launched a hanging breaking ball from Los Angeles Angels right-hander Cory Rasmus into the left-field seats to give the Orioles a 7-6 victory at Camden Yards.

As Rasmus (2-1) walked off the mound and the announced crowd of 36,882 erupted, Machado dashed around the bases, flipping his helmet in the air as he neared home plate before being mobbed by his jumping, screaming and sunflower-seed-throwing teammates.

“It was a blast,” said Machado, who gave the Orioles their eighth walk-off victory this season and third via a homer. “Once I hit it, I knew it was out. At that point, it was just excitement running through my body. The first one, got [it] out the way. I got chills rounding the bases.”

These get-their-money’s-worth Orioles have now played 15 extra-inning games this season and have won 12 of them, including seven straight. Channeling their inner 2012 squad -- which was 16-2 in extra innings -- the Orioles have gone beyond nine innings in three of their last four games, and won all of them.

“We don't think about it that way. We just go out there and play,” Machado said. “Once you go into extras, it's our bullpen in key situations. So we got to go out there and do what you got to do. That's how we see it.”

The dramatic homer -- Machado’s 11th of the season -- gave the Orioles their eighth win in their last 10 at home, putting them five games over .500 at Camden Yards for the first time since last September. The Orioles (59-46) are 7-4 since the All Star break, including a 6-4 record on their recent West Coast road trip, and they're 13 games over .500 for the first time since last August.

It was their third win in four games against the Angels (63-42); all four have been decided by two or fewer runs. Both clubs have explosive offenses and strong bullpens and would make for an even and interesting pairing if they were to meet in the playoffs.

“I think it’s a sign of two good bullpens,” Orioles manager Buck Showalter said. “You are talking about the run differential. But they are capable of putting a lot of crooked numbers on you. What the future of the season holds for us, I haven’t gone there yet. I’m looking forward to the day after [Wednesday], they are going to be somebody else’s problem for a while. They are a pretty impressive group.”

The Orioles held Tuesday’s lead heading into the late innings, but gave it back in the seventh on a grounder that should have been an inning-ending play.

With two outs, reliever Brad Brach hit Mike Trout with a pitch and then allowed a single to Albert Pujols that put runners on the corners. Showalter summoned left-hander Brian Matusz to face Josh Hamilton, who was 0-for-11 with seven strikeouts against Matusz in his career.

The move seemingly worked; Hamilton hit a grounder to shortstop J.J. Hardy, who fielded it and prepared to flip to second base, but second baseman Ryan Flaherty wasn’t there.

Flaherty had been playing closer to first base against Hamilton -- where he was supposed to be, Showalter said. Hardy ultimately realized Pujols would beat Flaherty to second base, so he threw to first. Hamilton was safe on the infield single, and Trout scored to tie the game.

“He’s not too far over. [Flaherty] told J.J., ‘I’m going to try to get there. I might be able to get there.’ And he tried to get there, and J.J. made the decision to throw to first,” Showalter said. “And hats off to Hamilton for running the ball out. And hats off to Pujols for getting out [to second] with a big enough lead to make him throw across the diamond.”

It was that kind of back-and-forth game between two of the best teams in the American League. The clubs combined for 17 runs in their three battles last week in Anaheim, Calif., with neither side scoring more than four in any game. Things were a little different Tuesday; 10 runs were scored before the fourth inning had ended.

Last Wednesday, right-handers Chris Tillman and Jered Weaver dueled in a game that Weaver and the Angels ultimately won, 3-2. Neither pitcher was as crisp Tuesday evening.

Weaver allowed a season-high six runs in five innings pitched. He allowed four walks and seven hits, including a solo homer to Adam Jones and a three-run shot by Nick Markakis that bounced off the right-field foul pole.

Jones’ blast was his 20th homer of the season, giving him at least 20 home runs in four consecutive seasons. It was Jones’ fourth longball in 11 games since the second half began.

Tillman didn’t fare much better than Weaver. The Orioles right-hander snapped his streak of four straight quality starts with his shortest outing since June 8 at Texas. Tillman threw just one clean inning, and allowed the Angels to score at least one run in four of the five innings he pitched.

“Not good enough. I felt good physically, made some good pitches but not consistent enough,” Tillman said. “You fall behind and leave a ball over the plate and make a mistake, and they're too good of a team to make mistakes against.”

His biggest miscue came defensively. With a runner on third base and one out in the second inning, Tillman knocked down a hard comebacker by David Freese, picked up the ball and rushed his throw. The ball carried to the backstop, allowing Howie Kendrick to score. Two batters later, Kole Calhoun hit a double to drive in Freese.

“I don't know what I was thinking,” Tillman said. “I should have taken my time a little bit more.”

The Angels picked up two other runs on productive outs, and Hamilton added his sixth homer of the season, a solo shot to center in the fifth. Tillman gave up five runs (three earned), six hits and a walk while striking out six batters.

The Orioles bullpen kept the Angels scoreless after the Hamilton’s single in the seventh. Tommy Hunter, Zach Britton, Darren O’Day and Ryan Webb (3-1) combined for 5 1/3 scoreless innings.

It was the Orioles’ typical formula for many of their 2014 wins: Hit homers, pass the ball to the stout bullpen and wait for the big game-winner. It is, in fact, very similar to what happened in 2012, when the Orioles made the postseason for the first time in 15 years.

“We have good chemistry in the clubhouse like we did back then and, obviously, we have a good bullpen as well,” Machado said. “We have kind of the same guys coming back. I think we can be a better team. I think we can be a little more focused. We’ve got our minds right where we need to go and where we need to get to.”

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