Against right-handers, Smith is a career .279 hitter with 65 home runs and 235 RBIs. His presence can help the Padres, who after being beset with injuries ended up with a heavily right-handed lineup. For the season the Padres hit .241 against righties.
"When we were at our best offensively, from the middle of 2012 to the middle of 2013, we had a balance of left and right, guys who could move around, who had power and speed," general manager Josh Byrnes said. "Seth Smith has done that very well, and hopefully he can do that for us."
Smith returns to the National League West after being selected by the Rockies in the second round of the 2004 First-Year Player Draft and breaking into the big leagues with Colorado. Smith has averaged 434 plate appearances per season since his first full season, in 2009, and most likely would do the same with the Padres.
"I had no idea, but as you can tell today, when you're with the Oakland A's, you know they're always looking to improve the club and looking to do what best puts them in position to win, so you never know what kind of exciting thing is going to happen," Smith said. "It's kind of exciting looking around and seeing all the moving pieces.
"I'm looking forward to joining the Padres and I'm excited about it. I love the NL West, and I know the stadiums and a lot of the pitchers. It's kind of the middle of the offseason, where you're starting to get revved up. This will help propel me to step up my offseason training."
Smith said he spoke briefly with Byrnes on Tuesday and didn't discuss his role in detail, but he is confident it will be a good situation.
"It seems I'm always in the situation where you don't know what's going to happen, but it always seems to work out and the at-bats find themselves, so it's not something I concern myself with," Smith said. "I show up prepared to play and I'm ready to play where they want me to play."
Smith also adds to an outfield that was depleted by injury last season but now looks crowded.
Right-handed-hitting left fielder Carlos Quentin, who has been productive when healthy, is coming off surgery on his right knee for the second straight year but is expected to be healthy for Spring Training. Lefty-hitting Will Venable batted .268 with a career-best 22 homers while playing right and center. The Padres are hoping for a healthy return from center fielder Cameron Maybin, who was limited to 14 games last season because of an injury to his left knee that didn't require surgery and an injury to his right wrist that did.
Also returning are left-handed-hitting Alexi Amarista, who was forced from the infield to the outfield because of the injuries, versatile right-handed-hitting Chris Denorfia and right-handed-hitting outfielder-first baseman Kyle Blanks.
"It's not that easy to find bats, guys who have done it," manager Bud Black said. "With Seth we're getting an experienced Major League hitter who has had success in our division and coming back to the National League, where he can be used as a starting outfielder or a left-handed threat off the bench; it's adds to our offensive strength. It adds to our depth, and in this day and age, you need depth."
The move also could set up the Padres for more dealing. Gregerson, 29, posted a 2.71 ERA over 66 1/3 innings in 2013 and for his Padres career was 17-22 with 16 saves, a 2.88 ERA and 352 strikeouts against 107 walks in 363 relief appearances over five seasons (2009-13).
Losing Gregerson means that the Padres are seeking bullpen depth. Byrnes said that the Padres could seek a hard-throwing lefty, but that they also have young candidates in house and could get bullpen help from someone who doesn't make the rotation.
Byrnes also noted that the trade has no financial implications. Smith and Gergerson each are in their third year of arbitration-eligibility. Smith made $3.675 million season, Gregerson $3.2 million.