The Beaver (Pa.) County Times is reporting that the Braves will also receive minor league shortstop Brent Lillibridge in the deal, while minor league outfielder Jamie Romak will be going to Pittsburgh along with LaRoche.
The trade was officially announced Friday.
The Pirates and Braves had been discussing a LaRoche-Gonzalez swap for weeks. Pittsburgh general manager Dave Littlefield was looking to upgrade an offense that ranked last in the National League with 141 home runs and a .397 slugging percentage.
LaRoche hit 32 homers and drove in 90 runs last season and finished in a tie for seventh in the National League with a .561 slugging percentage.
Gonzalez went 3-4 with 24 saves and a 2.17 ERA for the Pirates in 2006.
Gonzalez should help improve an Atlanta bullpen that went 25-23 with a 4.39 ERA last season and blew a league-high 29 saves.
Bob Wickman saved 18 games after coming over in a July trade with Cleveland, and the Braves picked up reliever Rafael Soriano from Seattle last month in a deal for starter Horacio Ramirez.
The Braves will go into 2007 with a new right side of the infield. Kelly Johnson and Martin Prado are the leading candidates to replace second baseman Marcus Giles, who signed with San Diego when the Braves declined to tender him a contract in December. Scott Thorman, who hit five homers in 128 at-bats with Atlanta last season, could replace LaRoche at first base.
During the course of the Pittsburgh-Atlanta talks, the Braves asked about center fielder Chris Duffy along with Gonzalez. But Littlefield reportedly was unwilling to part with Duffy or any of the Pirates' top young pitching prospects.
With Wickman set in the closer's role in Atlanta, it appears that Gonzalez will be used as a set-up man. Some baseball insiders are speculating that the Braves might be interested in flipping around Gonzalez as part of a second deal. The Yankees, among other clubs, have expressed interest in Gonzalez.
Jerry Crasnick covers Major League Baseball for ESPN Insider.