The contract is contingent on Pineiro passing a physical exam later this week, the sources said. The deal includes a player option for 2008 and $2 million in performance bonuses based on games finished, according to The Associated Press.
Pineiro, who pitched exclusively as a starter during his last four seasons with Seattle, is expected to work out of the bullpen for Boston. He could be given a chance to compete for the team's closer's job in spring training.
Jonathan Papelbon, who saved 35 games as a rookie for the Red Sox before going down with shoulder problems, is expected to move to the starting rotation in 2007. Veterans Mike Timlin and Julian Tavarez and youngsters Manny Delcarmen and Craig Hansen could also be in the mix for the closer's job when the Red Sox arrive in spring training in Fort Myers, Fla., in February.
Pineiro, 28, went a combined 30-18 for the Mariners in 2002-03, but has tailed off badly over the last three seasons. His ERA has risen from 3.78 to 6.36 since the 2003 season, and his ratio of strikeouts per nine innings has declined from 7.10 to 4.73 over the past three years.
Some scouts, however, think that Pineiro can do a better job of maintaining his velocity and effectiveness in shorter doses out of the bullpen.
Pineiro made a base salary of $6.8 million last season, but became a free agent in December when the Mariners declined to offer him a contract rather than have him go to salary arbitration.
While the Red Sox have considered the idea of using Papelbon as a closer again next year, they're leaning strongly toward pitching him in the rotation. Red Sox officials think that Papelbon has a better chance of staying healthy and having a more productive future as a starter.
Jerry Crasnick covers Major League Baseball for ESPN Insider.