SAN DIEGO -- Since being traded away from San Diego in July, Scott Hairston's oldest son, 4-year-old Landon, has persistently pestered his father as to when he would play for the Padres again.

"I kid you not, Landon asks me that all the time," Hairston said on Friday. "I told him it was probably never going to happen."

As it turns out, the elder Hairston was wrong.

In the first major trade of first-year general manager Jed Hoyer's tenure, the Padres officially sent third baseman Kevin Kouzmanoff and Minor League second baseman Eric Sogard to the A's for Hairston and Minor League outfielder Aaron Cunningham on Saturday.

Hairston, reached by phone from his home in Arizona, said Friday that Kouzmanoff had contacted him earlier in the day and said he was being traded to the A's. Hairston, at that point, was happy to have his friend coming to the A's.

He didn't know at the time that he was on his way back to San Diego, where he played for parts of three seasons for the Padres until being traded to the A's on July 5 for three pitchers.

"For me to come back is just unbelievable," said Hairston.

Hairston, who like Kouzmanoff is arbitration-eligible, never wanted to leave the Padres. He was so stunned by the trade in July that he wept when talking to reporters.

"We really didn't want to give up Scotty. But for us, this is a move looking beyond this year," said then-Padres general manager Kevin Towers after the trade.

The Padres had been looking to add a right-handed-hitting outfielder all offseason and someone who could platoon in center field with Tony Gwynn. Oddly enough, Hairston's older brother, Jerry, a free agent, had been in talks with the Padres.

"My head has been spinning the whole day," Hairston said. "I never wanted to leave. ... I loved it here, my family loved it, the fans, the front office, were all great. Everything was clicking for me. I never wanted to play anywhere else."

Hairston hit .236 with seven home runs and 36 RBIs with the A's. He hit .299 with 10 home runs and 29 RBIs in 56 games before the trade.

Hairston is a career .287 hitter against left-handed pitchers, something that surely had a lot of appeal to the Padres. In 610 at-bats with the Padres, Hairston hit 35 home runs with 80 RBIs.

In his time with the Padres, Hairston showed that a right-handed hitter can have success at PETCO Park, a stadium with a reputation as a pitching-friendly ballpark. Hairston is a career .285 hitter with 19 home runs and 49 RBIs in 344 at-bats at PETCO Park.

Hairston missed time at the end of the regular season with pain in his hip and back. But he said he had a physical by the A's on Dec. 12 and everything checked out fine. As of Friday afternoon, he hadn't been informed if he would need another physical.

Cunningham, who turns 24 in April, will already be joining his fourth organization. He's a right-handed hitter who batted .302 with 11 home runs and 48 RBIs in 334 at-bats with Triple-A Sacramento.

He's hit .211 with two home runs and 20 RBIs in 133 at-bats with the A's over the last two seasons. It's not known if he'll platoon with Will Venable in right field or if he will begin the season with Triple-A Portland.

Outfielder Kyle Blanks, presumably, will start in left field.

As for third base, the Padres parted with a player in Kouzmanoff who drove in a career-best 88 runs last season, his third with the Padres. He also set a National League record for fielding percentage for a third baseman (.990).

There were some in the Padres organization who felt Kouzmanoff had reached his ceiling as an offensive player. He hit 18, 23 and 18 home runs the past three seasons and his on-base percentage in that span was .309.

The trade allows Chase Headley to slide back to his natural position. Headley was asked before the 2008 season to move to the outfield so that he and Kouzmanoff could be in the lineup together.

"For me, it would be great to get back to third base. It's where I'm the most comfortable and where I feel I can make the biggest impact to help win games," Headley said Friday from his home in Tennessee.

"I was happy with what I was able to accomplish out there [in the outfield]. But it was a lot of work when you haven't played that position before. You don't want to just be an average Major League player. You want to be the best player you can be. ... I just think it makes a lot more sense being there [at third base] than in the outfield. For me, it will be fun."

Headley played 28 games at third base a year ago and had a .907 fielding percentage. He also played seven games there in 2008 and five at third base in 2007.