Moving quickly to find a new closer, the Oakland A's acquired right-hander Jim Johnson from the Baltimore Orioles on Monday.
Baltimore received infielder Jemile Weeks and a player to be named.
Oakland's 2013 closer, right-hander Grant Balfour, is currently a free agent and is not expected to re-sign with the A's.
Johnson, 30, led the American League in saves each of the past two seasons, going 50-for-59 in save chances this year after finishing 51-for-54 in 2012.
The Orioles decided to deal Johnson rather than go to arbitration with him this winter, a process that likely will land him a salary in excess of $10 million.
"It's really about the allocation of resources," Orioles executive vice president Dan Duquette told the Baltimore Sun. "And to have a competitive team, you have to have proper balance throughout your club. And this is our intent with the trade: to balance our roster and allocate our resources properly and have a competitive team in 2014."
Weeks, 26, might get an opportunity to play second base for Baltimore, but he ran out of chances in Oakland. Once a highly touted prospect, Weeks fell off the radar the past two seasons. He hit .221 with no power and lowly .305 on-base percentage while playing 118 games for Oakland in 2012, stats that led to him spending almost all of 2013 back in the minors.
In eight games for the A's this year, Weeks went 1-for-9 with five strikeouts and no walks. With Triple-A Sacramento, Weeks batted .276 with a .376 on-base percentage, a .369 slugging percentage, four homers, 40 RBIs and 17 stolen bases in 130 games.
Earlier Monday, the A's agreed to a two-year, $22 million deal with free agent left-hander Scott Kazmir, multiple media outlets reported.