Source: Pirates to add Scott Olsen

LAKE BUENA VISTA, Fla. -- The Pittsburgh Pirates have reached agreement with free-agent left-hander Scott Olsen on a one-year contract, a baseball source told ESPN.com. Olsen will earn a base salary of about $500,000, and could make an additional $3 million in incentives based on starts.

The deal includes a 2012 club option for about $4 million, the source said.

If healthy, the 26-year-old Olsen is expected to fill a spot in Pittsburgh's rotation after Paul Maholm, James McDonald and the newly acquired Kevin Correia.

The Pirates, who also have Jeff Karstens, Charlie Morton and Brad Lincoln in the mix for starting jobs, recently traded lefty Zach Duke to the Arizona Diamondbacks for a player to be named.

Pittsburgh general manager Neal Huntington is trying to upgrade a starting rotation that went 34-84 with a major league-worst 5.28 ERA last season.

Olsen, who underwent shoulder surgery in 2009, posted a 5.56 ERA in 81 innings with Washington in 2010. He has a career 37-49 record with a 4.85 ERA in six seasons with the Florida Marlins and the Nationals.

The Pirates recently expressed interest in lefty Jorge De La Rosa before he re-signed with the Colorado Rockies, and have been linked to free agents Brandon Webb and Jeff Francis, among others.

Jerry Crasnick is a senior baseball writer for ESPN.com.