The rebuilding Orioles receive third baseman Josh Bell and pitcher Steve Johnson from Double-A Chattanooga.
Sherrill has 20 saves for last-place Baltimore and gives Los Angeles, with the best record in the NL, a left-handed complement to All-Star closer and Burke County High graduate Jonathan Broxton. Sherrill is expected to join the Dodgers today in Atlanta.
"It's a great move for us," Broxton said in St. Louis. "It gives us an extra arm, and he's got some innings under his belt.
An AL All-Star last season, the 32-year-old Sherrill is 0-1 with a 2.40 ERA. He has limited opponents to a .219 batting average in 2009.
"I expect he will help us. Obviously, Broxton is our closer," Los Angeles manager Joe Torre said before his team played the Cardinals. "But we'll use him late in the game -- eighth, ninth inning. It gives us a backup, an experienced backup."
Meanwhile, the Chicago Cubs landed a new left-hander for their bullpen, acquiring John Grabow from the busy Pittsburgh Pirates in a five-player trade Thursday.
Locked in a tight race atop the NL Central, the Cubs sent right-handers Kevin Hart and Jose Ascanio and minor league infielder Josh Harrison to Pittsburgh for Grabow and lefty Tom Gorzelanny.
Grabow, a top situational lefty, is 3-0 with a 3.42 ERA in 45 appearances.