Dan Uggla is likely the most sought after bat available on the trade market -- at least one that is readily known as available. Uggla's power at the prime position of second base makes him extremely valuable. There are certainly better fits than Atlanta, with Martin Prado entrenched as the every day second basemen.
The Braves could reasonably trade for Uggla and move either him or Prado to left field. Prado has played there in the past, mostly in winter ball, and is said to be at least decent in the outfield. Uggla is one of the worst defensive second basemen in baseball, so it may make more sense to maintain a strong infield defense with so many ground ball starters on the staff. Uggla has played the outfield in the minor leagues, which was many years ago, so he would be in a transition phase as a left fielder, which could lead to some poor routes and missed cut off men as he re-learns the position.
Even with the poor defense, Uggla does provide usefulness with his bat. His bat, while a plus bat as a second basemen, would still play above average in left field. He is a perennial 30 home run hitter who has not had an on base percentage lower than .354 in any of the past three seasons. In addition, last year was his best overall year as he posted a career high .381 wOBA and a career high 33 home runs.
The problem with Uggla arises with his age. He is already 31-years-old and is looking for a four year deal. This would bring him to 35, and it is hard to imagine him staying as productive over the next four years as he has been over the previous four. If the Braves trade for him, it would be a waste if they were unable to extend his contract. He has always had a high strikeout rate, which is also another red flag as the years continue to add on.
In terms of what would needed to be traded, something like left-handed starter Carlos Perez and either second basemen Mycal Jones or right-handed starter J.J. Hoover may be able to land Uggla, depending on how high other teams are willing to bid for his services. He is not the type of player that would command a top flight prospect, but the Marlins could land two prospects with potential. The Marlins could worry about trading Uggla in the division, which could force them to ask the Braves or Nationals -- if they are a real option as well -- to pony up more prospects or even a Major Leaguer.
So, is Dan Uggla a real option for the Braves? Yes. They would give up talented players but get a legitimate right-handed power threat back. Should he be a serious option? No. His age and lack of a real position are big enough deterrents for the Braves to focus their energy elsewhere. Looking for a defensive center fielder and an affordable powerful left fielder with experience at the position would be wiser. Uggla sounds good right now, but a four year contract would sound equally as bad once Uggla is 35 misplaying balls in the outfield or infield.