BOSTON -- The Red Sox are on the verge of landing the key piece to their bullpen that general manager Theo Epstein has been searching for all winter.

Bobby Jenks, the closer who was non-tendered by the White Sox earlier this month, has agreed to a two-year, $12 million contract with Boston, a person familiar with negotiations told The Associated Press.

The person spoke on condition of anonymity because the deal was not yet final. The agreement was first reported by ESPN.com.

The Red Sox have yet to announce the addition of Jenks, as the club does not comment on any transaction until it is official.

Boston has a four-time All-Star closer in Jonathan Papelbon, who is under contract for one more season. By adding Jenks with Papelbon and Daniel Bard, the Red Sox could have one of the best 1-2-3 late-inning punches in the league.

The other possibility is that the Red Sox could trade Papelbon, who is eligible for arbitration and could make close to $11 million in 2011. Earlier this offseason, Epstein tried to sign future Hall of Fame closer Mariano Rivera away from the Yankees. If that move had been completed, he would have either traded Papelbon or non-tendered him. Instead, Rivera returned to New York.

Initial efforts to reach Jenks and his agent, Greg Genske, were unsuccessful.

While Epstein pushed hard for other free agents like Scott Downs, Matt Guerrier and Jesse Crain, Jenks wasn't a name linked to the Red Sox on the rumor mill, perhaps because of Papelbon's presence and the assumption that Jenks was likely to land a closing job.

Much like Papelbon, Jenks had a down year in 2010, posting a 4.44 ERA in 55 games. The righty converted 27 of 31 save opportunities. Jenks' season ended on Sept. 4 because of issues in the ulnar nerve in his throwing elbow.

Jenks would be the latest significant addition to a Boston team that has added star hitters Adrian Gonzalez and Carl Crawford to the roster in the last couple of weeks.

The 29-year-old Jenks broke into the Major Leagues in 2005, starting as a setup man but emerging into the closer by that October, when the White Sox won the World Series. He has made 329 appearances in the Majors, posting a 3.40 ERA and notching 334 strikeouts over 341 2/3 innings. He posted a career-high 41 saves in '06 and came back with 40 more the following year.