SAN DIEGO -- The news that the Padres had acquired him from the Milwaukee Brewers for Jody Gerut on Thursday morning was shocking for Tony Gwynn Jr. to hear.

That he heard it first from his dad, Padres legend Tony Gwynn, was crazier.

Then his day ended on an even more surreal note, when Gwynn Jr. scored the winning run as the Padres rallied in the ninth inning for a 3-2 victory over the San Francisco Giants.

"Even at this point, it still hasn't kicked in that I'm here," Gwynn said. "It probably won't until kick in until I get into my bed (Wednesday night) and am like, 'Wow, I'm home and it's only May.' "

Stepping to the plate in the ninth, Gwynn received a standing ovation from the Petco Park crowd of 19,921. But Gwynn, who drew a walk in his Padres' debut, said he wasn't overcome with emotion because he was so drained after traveling from Nashville, Tenn., to Portland, Ore., late Wednesday night. Gwynn, who was playing for the Brewers' Triple-A Nashville affiliate, raced back to the airport Thursday afternoon to catch a flight to San Diego, arriving nine minutes before the 7:05 p.m. game.

"I feel like it helped because I didn't really have any emotion," Gwynn said. "You just see the ball, hit the ball. If it's in the zone, you put a good swing on it and see what happens."

There was plenty of emotion on the other end of the phone when Tony Gwynn called from Fort Worth, Texas -- where the San Diego State baseball coach is leading his team in the Mountain West Conference tournament -- to inform his son that the Padres had acquired him. In a radio interview before the game, Gwynn Jr. said his dad "was yelling into the phone like he had won a national championship."

"It was more so him talking and me not believing at first," Gwynn Jr. said Thursday night.

Gwynn Jr. -- whose No. 18 jersey number with the Padres is one less than his father's retired No. 19 -- said he was excited for the opportunity. After suffering a shoulder injury before spring training that limited him to 15 games, Gwynn -- who is out of minor league options -- accepted an assignment to Nashville after he was waived and went unclaimed. He played in 38 games for Nashville and was hitting .309 with 15 stolen bases.

"Dad's thrilled," Tony Gwynn told the Associated Press earlier in the day. "This is like a bolt out of the sky. You just didn't expect that. I'm thrilled."

General manager Kevin Towers said the Padres were happy to replace Gerut, who is eligible for free agency after the 2010 season, with a player under the team's control for five seasons. Gerut signed a one-year, $1.775 million contract this offseason, making him the Padres' fifth-highest-paid player. The trade will save the Padres more than $1 million, as Gwynn Jr. earns $405,000.

Towers and manager Bud Black said Gwynn and Gerut are similar players, with the former having better speed and the latter providing more power. Both play all three positions in the outfield.

"Tony's probably a little fleeter afoot and covers more ground defensively," Black said. "His style might work well in this park."

Gerut said he hoped he would have more success in Milwaukee's Miller Park. The 31-year-old signed a minor league deal with the Padres before last season after missing more than 2 1/2 seasons with knee injuries. He stormed onto the scene in May 2008 and hit .296 with 14 homers last year.

But Gerut was off to a slow start this season, hitting .221 with four homers. His playing time had been reduced because of Scott Hairston's hot start.

"I've been traded before. It doesn't make it any easier," Gerut said. "I'm very grateful to the Padres for the opportunity to get my feet wet again, to get myself re-established. … The Padres will always have a special place in my career."