THE REAL BASH BROS.

Jason Giambi watched from the bench as Jeremy Giambi followed his big brother’s homer with one of his own three innings later.

As Jeremy rounded the bases, Jason got high-fives and fist bumps in the dugout from Oakland Athletics teammates. Then Jeremy crossed the plate to a second wave of congratulations, including a quick rap of the fists from his brother.

The two became the eighth set of brothers on the same team to homer in the same game, on May 8. And they did it in Anaheim, near their hometown of West Covina, in front of their parents and younger sister.

The whole family is relishing the brothers’ first chance to play together.

“We’re having a great time. We’re having a ball,” Jason said.

He played against his brother last season in Kansas City before Oakland united the two by trading for Jeremy in February and making him a reserve outfielder and designated hitter.

“It’s nice to have somebody around to hang out with,” Jason said. “We grew up with each other, watched each other’s swings, so he can help me out a lot. We talk to each other all the time.”

The good vibrations could soon get even better.

Jason might be heading for his first All-Star game, hitting 16 home runs and driving in 47 runs going into the weekend, both AL highs.

After a shaky start that produced a 10-day demotion to the minors -- and coincided with Jason’s only slump of the season -- Jeremy made 12 starts in a row in right field for an ailing Matt Stairs and went 15-for-46 (.326) with two doubles, four homers and 17 RBIs.

“From the first day I went to Sacramento, I played well and put the pressure on them to call me back up,” Jeremy said, referring to his stint in Triple A. “Since I’ve been back, I’ve had an opportunity to play every day and get in a little bit of a groove.”

So has Jason. Following his brief slump (7-for-33, .212), he took off again, going 17-for-45 (.378) since his brother’s return.

“Hey, if I’m the reason, hopefully I can stay up here the rest of the year and watch him have an unbelievable year,” Jeremy said with a laugh.

When he got called back up on May 5, Jeremy moved back in with his brother in their rented digs in nearby Hayward. They take turns driving each other to the ballpark, typically hitting a drive-through restaurant on the way, and often going out on the town together for dinner afterward. They’ve also bought a house in Las Vegas where they plan to live in the offseason.

“For the most part, we do everything together, and in a way I feel like a kid again,” Jeremy said.

Because of their age difference--Jason is 29, Jeremy 25--they didn’t play together on the same teams while growing up.

“He was a senior in high school and I was a freshman but he would always include me in what he was doing, and that’s kind of where we’re at again,” Jeremy said.

Oakland manager Art Howe said the two have formed a healthy support system.

“They know each other very well,” he said. “They study films of their hitting and they’re always trying to help each other. They’re very positive and very supportive.”

Oakland, 21-21 going into the weekend, two games behind first-place Seattle in the West Division, has come to count on them in different ways.

Jason, the regular first baseman since the A’s traded Mark McGwire to St. Louis in 1996, has become the team’s emotional leader and its main offensive force. He has built on last season, when he had career highs in batting (.315), home runs (33) and RBIs (123).

Jason said he’s never been more confident and comfortable.

“I’m older and smarter and I’ve learned a lot,” he said. “I’ve taken things that people taught me and kind of turned them into my own.”

Jeremy said he has a new appreciation for his brother’s skills now that he sees them every day.

“He’s gotten better every year and hopefully, if I get my opportunity to play every day, I can put up some numbers too,” Jeremy said.

Jason said Jeremy’s time will come.

“He’s his own player and some day, he’s going to achieve that when he becomes an everyday player,” Jason said.

Since rejoining the A’s, Jeremy has established himself as the A’s top outfield reserve. His newfound consistency at the plate has also led to stints at designated hitter in place of injured John Jaha.

That’s what general manager Billy Beane envisioned when he made the trade for the younger Giambi. “This wasn’t about nepotism. The kid can flat-out hit,” he said.

Given the nature of baseball and economics, the brothers aren’t looking very far ahead at their future on the same team. But they’ll enjoy it while it lasts.

“We’re making a lot of great memories,” Jeremy said. “Our family gets to come up and see us at the same time instead of going to different cities, so it’s easier on them. It’s just been fun and exciting from the first day of spring training until now and hopefully it will continue for the rest of the year.”