"The Arizona Diamondbacks announced Thursday they agreed to terms with left-hander Zach Duke on a one-year contract with a mutual option for 2012.

Duke was acquired from the Pirates last week and had until Friday to reach a deal with the Diamondbacks.

Duke, who turns 28 in April, had a career-worst 5.72 ERA in 159 innings this season, one year after posting a 4.06 ERA in 213 innings in 2009. He has a 4.54 ERA in parts of six seasons in the majors.

"I love a challenge," Duke said last week after the trade. "From what I understand from the Diamondbacks, they're committed to winning this year. I want to do whatever I can to help the team win and I know I'm going to be prepared to go out and bust my butt.""