PHOENIX -- The Diamondbacks agreed to terms with left-hander Oliver Perez on a two-year contract Friday, adding another left-hander to an already crowded bullpen, FOX Sports' Ken Rosenthal reported.
Perez, 32, spent his first nine major league seasons primarily as a starter before being converted into a reliever in 2012, the first of two seasons in the Seattle bullpen. He was 4-6 with two saves and a 3.16 ERA with the Mariners, striking out 98 in 82 2/3 innings. Lefties hit .238 against Perez last season.
"At least he will give hitters an uncomfortable at-bat," one veteran scout said of Perez.
D-backs general manager Kevin Towers was with San Diego when Perez broke into the major leagues as a starter in 2002 before spinning Perez off to Pittsburgh with Jason Bay for Brian Giles. Towers withheld comment Friday.
Joe Thatcher could be the odd man out if Perez sticks. Thatcher, acquired with Matt Stites from San Diego in the Ian Kennedy deal last July 31, struggled in his role as a left-hander specialist after his acquisition. He was 0-1 with a 6.75 ERA in 22 appearances for the D-backs, giving up seven runs and 12 hits in 9 1/3 innings.
Thatcher gave up a double off the right-field fence by left-handed hitting Josh Reddick on Thursday at Salt River Fields. Left-hander Joe Paterson, who had such a strong season in 2011 before spending most of the last two seasons at Class AAA Reno, gave up a three-run home run to Kansas City's Mike Moustakas, a right-handed hitter, on Wednesday.
Thatcher is to make $2.375 million this season after signing a deal to avoid arbitration. Perez played for $1.5 million in 2013. Terms of his D-backs deal were not immediately available.
Paterson, Eury De La Rosa and Santos Rodriguez are the other left-handed relievers on the 40-man roster. The D-backs carried two lefties in the bullpen early last season -- Matt Reynolds and Tony Sipp -- but Reynolds is expected to miss most if not all of the season after undergoing Tommy John surgery and Sipp was let go in the offseason.
With the addition of Perez, the D-backs are running out of room. Addison Reed, J.J. Putz. Brad Ziegler, David Hernandez and Josh Collmenter and Randall Delgado are expected to open the season in the bullpen, and Will Harris did solid work as a setup man in 2013.
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