UPDATE #2 10:25am ET: It seems there is a fifth player headed to Arizona. Low-A first baseman Brandon Drury is also part of the trade, according to Buster Olney of ESPN:
There is a fifth player going to the deal for Arizona -- Brandon Drury. milb.com/milb/stats/sta…— Buster Olney (@Buster_ESPN) January 24, 2013
UPDATE 10:10am ET: The full details of the trade have been uncovered by Mark Bowman of MLB.com.
The Braves will get Justin Upton and third baseman Chris Johnson from the Diamondbacks.
In exchange, the D'Backs will receive utility man Martin Prado, right-hander Randall Delgado, and a pair of prospects: shortstop Nick Ahmed and right-hander Zeke Spruill.
The package heading to Arizona will be built around right-hander Randall Delgado, according to Ken Rosenthal of FOX Sports.
Justin joins his brother B.J. Upton, who the Braves signed earlier this offseason, in Atlanta. The team's outfield will now consist of the Upton brothers and Jason Heyward. The trio, who are all 28 or younger, combined to account for 168 extra-base hits, including 72 home runs, and 70 stolen bases in 92 attempts last season.
Despite his six years of experience at the major league level, Upton is still only 25 years old. The slugger has hit .278/.357/.475 during his time with the Diamondbacks as the team's primary right fielder.
Last season Upton hit .280/.355/.430 with 24 doubles, four triples, 17 home runs and 18 stolen bases in 26 attempts.
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Upton has three years remaining on his six-year, $50 million contract. The deal will see him earn $9.75 million in 2013, $14.25 million in 2014 and $14.5 million in 2015.
Delgado is considered one of baseball's top pitching prospects. The 22-year-old appeared in 18 games, including 17 starts for the Braves last season, maintaining a 4.37 ERA with 7.4 strikeouts and 4.1 walks per nine innings. Over six seasons at the minor league level the right-hander owns a career ERA of 3.60 with 9.6 strikeouts and 3.4 walks per nine innings.