Pittsburgh adds the veteran left-hander on a minor-league deal.
The Bucs were rumored to be close to a deal with the 30-year-old southpaw on Monday evening, but with the amount of time discussions have taken with Francisco Liriano since his first "close to a deal" rumor emerged with the club, it was reasonable to assume that a deal might not be finalized for some time.
Sanchez will report for camp in Bradenton, Florida, next week looking to bounce back from a career-worst 2012 season.
Related: Still No Deal Between Bucs, Liriano
The Kansas City Royals acquired by the left-hander from the Giants last winter in exchange for Melky Cabrera in the hope that Sanchez could anchor their weak rotation. Sanchez was terrible out of the gate and only got worse at the season progressed, leading to a Sanchez/Jeremy Guthrie swap with the Rockies at the trade deadline.
Sanchez did not improve once in Colorado, his walk rate continuing to climb as his strikeout rate dropped. The southpaw ended up with an 8.07 ERA, 7.4 BB/9 rate, and 1.5 HR/9 rate over 64⅔ innings in 15 starts on the year, missing the final two months of the season with inflammation in his biceps.