5:30 p.m. update: The Braves traded left fielder Justin Upton to San Diego on Friday in a six-player deal that adds prospects to a depleted farm system and subtracts the team leader in home runs and RBIs from an already anemic Atlanta offense.

In return for Upton and minor-league pitcher Aaron Northcraft, the Braves received four young players, led by left-handed pitching prospect Max Fried. Recently ranked the Padres’ No. 3 prospect, Fried likely will miss all of next season after undergoing elbow surgery in August.

Also coming to the Braves: second baseman-third baseman Jace Peterson, the only Padre in the deal who has played in the majors; third baseman Dustin Peterson; and speedy outfielder Mallex Smith.

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The person, speaking on condition of anonymity because the teams had not announced the deal, said the Braves would receive a group of prospects. Among the players discussed were left-hander Max Fried, shortstop Jace Peterson and third baseman Dustin Peterson.

The Padres already made two huge trades in recent days, acquiring slugger Matt Kemp from the Los Angeles Dodgers and former AL Rookie of the Year Wil Myers from the Tampa Bay Rays.

Now, San Diego has picked up one of baseball's top right-handed power threats in Upton, who will earn $14.5 million in the final year of his contract. He had 29 homers and 102 RBIs last season.

In all likelihood, the Padres are not done dealing yet, with a glut of outfielders on the roster.

In contrast to San Diego's win-now approach, the Braves are in rebuilding mode after failing to make the playoffs last season and are aiming toward the opening of their new suburban stadium in 2017. New general manager John Hart has dealt two of the top hitters from a lineup that already had trouble scoring runs, trading Jason Heyward to the Cardinals.

Upton and Heyward are heading into the final year of their contracts, and the Braves were not willing to risk losing them while getting nothing in return.

With a solid pitching staff in place, the Padres have taken huge steps to pump up the major leagues' worst offense under their new general manager, A.J. Preller.

The trade for Upton came less than 24 hours after the Padres finalized a five-player trade with the Dodgers. The biggest name in that deal was Kemp, a two-time All-Star whose 182 homers rank fourth in Los Angeles Dodgers history.

The trade of Upton had been expected since the Braves signed outfielder Nick Markakis to a $44 million, four-year deal. The newcomer will take over for Heyward in right field, while Evan Gattis is expected to move from catcher to replace left fielder Upton.

Gattis, though, has also been mentioned in trade talks.

The deal breaks up the Upton brothers, whose two years together in Atlanta did not live up to expectations.

With much fanfare, the Braves signed B.J. Upton to a $75.25 million, five-year deal before the 2013 season and landed his younger brother in a blockbuster deal with Arizona. While Justin had two solid seasons, hitting 27 homers with 70 RBIs in his Braves debut, B.J. has been one of the biggest free-agent busts in baseball history.

This past season, the older Upton hit just .208 with 12 homers and 35 RBIs, though that was actually an improvement on his 2013 performance — .184, nine homers and 26 RBIs.

Atlanta would undoubtedly love to cut ties with B.J. Upton, as well, but it's unlikely that anyone would be willing to take on the final three years of his contract, even with the Braves assuming a substantial portion of the estimated $45 million he is still owed.

The 20-year-old Fried looks to be the biggest catch in the deal for the Braves, though any payoff is years down the road.

The seventh overall pick in the 2012 amateur draft, Fried pitched only five games last season between Rookie ball and Class A before lingering pain in his elbow forced him to undergo Tommy John surgery. He will miss a good portion of 2015 coming back from the reconstructive surgery, slowing his progress toward the majors.

Jace Peterson was expected to be the lone player coming to Atlanta with any big league experience. The 24-year-old hit just .113 in 27 games for the Padres last season.