But the acquisition also shuffles the projected 25-man roster to the point where it could mean skipper Don Wakamatsu will exit Spring Training with an 11-man pitching staff.
"In going through the process and in studying what teams were doing this offseason and watching what [general manager] Jack [Zduriencik] was doing up in Seattle, I believe in the moves he's made and where the team's going and the roster that's being built," Garko said on a conference call from his Phoenix-area home.
"I'm just really excited to be a part of it."
Garko, 29, combined to bat .268 with 13 doubles, 13 home runs and 51 RBIs in 118 game with the Cleveland Indians (78 games) and San Francisco Giants (40 games) in 2009. Garko, a career .279 hitter, hit a career-high 21 home runs in 2007 and tallied 90 RBIs in 2008.
Most important for the Mariners' purposes are Garko's stats against left-handed pitching. He is a career .313 hitter against southpaws with a career OPS of .887 against lefties.
The Mariners traded for left-handed-hitting first baseman Casey Kotchman earlier in the offseason, presumably to take advantage of his above-average defense while getting him on track with a full slate of at-bats following a few seasons in bench roles for Atlanta and Boston.
Now it appears that Garko will play some first base and take some DH at-bats away from Milton Bradley, which could make it necessary for the Mariners to keep a reserve outfielder, most likely Ryan Langerhans, on the roster in addition to the likely starters against left-handers: newly acquired Eric Byrnes, Franklin Gutierrez and Ichiro Suzuki.
Since the team also has Ken Griffey Jr. as a part-time DH and occasional outfielder and will carry two catchers and an infield that consists of Garko, Kotchman, second baseman Jose Lopez, shortstop Jack Wilson, third baseman Chone Figgins and utility man Jack Hannahan (or Matt Tuiasosopo), there would only be room for 11 pitchers.
"That's the way it slots out right now, but you just don't know," Wakamatsu said. "So many things can happen in Spring Training, and you'd always rather deal from a position of strength than one of weakness. As manager you can never have too many. It's a good problem to have.
"Plus with Felix Hernandez and Cliff Lee as your No. 1 and No. 2 starters, you'd like to think there's some benefit there and that maybe we'll have that luxury at the top of the rotation to do that."
Garko was a catcher in college at Stanford, won the Johnny Bench Award as the best at the position in the nation in 2003, and caught through Triple-A. While he projects to be the club's backstop in emergency situations only, he said he talked to Zduriencik about getting reps behind the plate in Spring Training in Peoria, Ariz.
"It's there, in terms of giving Don an opportunity to make some moves in games," Garko said. "I think it's important for us to have that third catcher."
Garko was originally a third-round pick by the Indians in the 2003 First-Year Player Draft. He will reportedly earn an additional $25,000 each for 325, 350 and 375 plate appearances in 2010 and would then get $50,000 apiece for 425, 450 and 475 plate appearances, and $100,000 each for 500, 550 and 600 plate appearances.
He said he's looking forward to rejoining former Indians teammates Lee and Gutierrez, with whom he played when the Indians lost to the Boston Red Sox in seven games in the 2007 AL Championship Series, and to hopefully once again play for a contending team.
"The important thing for me was to find a role on a team that I felt played to my strengths," Garko said. "I wanted to return to the American League. I felt like I'm a better fit over there.
"Every player's dream and goal is to win, and I think we have that opportunity here."
To make room on the Mariners' 40-man roster, right-handed pitcher Gaby Hernandez was designated for assignment. The Mariners now have 10 days to trade, release or outright Hernandez to the minors. Hernandez was acquired from Florida in exchange for lefty reliever Arthur Rhodes on July 31, 2008.