Santana, 32, signed a four-year deal with Minnesota worth $54 million in the offseason. He was 14-10 last season with a 3.95 earned-run average in 31 starts for the Twins with a strikeout-to-walk ratio of 179-63.
This spring, Santana was 3-1 in five starts with a 1.89 ERA and set to pitch the second game of the season for the Twins against the Detroit Tigers on April 8. Now, he won't be taking the field for the first half of the season.
"This is unexpected news for me and my family," Santana said in a statement issued by the Players Assn. apologizing for the positive test. "I am very disappointed that I tested positive for a performance-enhancing drug. I am frustrated that I can't pinpoint how the substance in question entered my body. I would never knowingly take anything illegal to enhance my performance. What I can guarantee is I never knowingly took anything illegal to enhance my performance. That's just not me, never has been and never will."
Santana, born in the Dominican Republic, began his Major League Baseball career with the Angels, where he spent 2005-12 before he was traded to the Kansas City Royals. He then signed a one-year deal with the Braves last year before joining the Twins.
Mike Pelfrey is expected to take Santana's spot in the rotation.
"All I can do now is continue to work hard, and when the suspension is up, come back to doing what I love," Santana said.
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