Atlanta Braves acquire Justin Upton for a package of players that includes All-Star Martin Prado

More than a year after the Arizona Diamondbacks began shopping outfielder Justin Upton, they finally traded him Thursday morning to the Atlanta Braves for a package that includes All-Star third baseman Martin Prado and four prospects, sources confirmed to Yahoo! Sports.

The deal concludes a whirlwind of activity surrounding the 25-year-old, who two weeks ago rejected a trade to the Seattle Mariners. While the Diamondbacks believe Seattle's offer was the best they received, they settled for Atlanta's despite Prado's impending free agency after the 2013 season.

Atlanta, meanwhile, celebrated its double-Upton outfield and the acquisition of the right-handed power bat it so coveted. After signing Upton's older brother, B.J., to a five-year, $75 million contract this offseason, the Braves struck a deal for Justin that one general manager called "a coup."

While he is coming off the worst season of his career, Upton is still a considerable talent under a friendly contract: three years at $38.5 million. Not only does he give the Braves arguably the best outfield in baseball, with his brother and Jason Heyward, he helps balance a lineup that should look something like this: Andrelton Simmons, Heyward, Justin Upton, Brian McCann, B.J. Upton, Freddie Freeman, Dan Uggla and perhaps a third-base platoon of Juan Francisco and Chris Johnson, who came from Arizona with Upton.

[Also: Window closing on aging, fragile Phillies]

Going back to Arizona, as first reported by MLB.com, are Prado, right-handed pitching prospects Randall Delgado and Zeke Spruill, shortstop Nick Ahmed and first baseman Brandon Drury.

The Diamondbacks' addition of Prado this season strengthens their lineup as well as eases an outfield glut that worsened upon the signing of free agent Cody Ross. Now Arizona will try to find at-bats for Ross, Adam Eaton, Gerardo Parra and Jason Kubel, though a source said the team will continue to consider offers for Kubel as well.

Upton is perhaps the biggest piece to move in an offseason full of big-name trades, from Jose Reyes to Shin-Soo Choo, R.A. Dickey to James Shields. The Diamondbacks can only hope this trade goes as well for them as it did for the last team to engage in a seven-player deal with the Braves.

In 2007, for Mark Teixeira and Ron Mahay, the Texas Rangers received Elvis Andrus, Matt Harrison, Neftali Feliz, Jarrod Saltalamacchia and Beau Jones.

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