Aybar for Andrelton

In Simmons, the Angels acquired one of the best shortstops in the game (Sports On Earth)

Who would you rather have; A 31 year-old shortstop (32 next year) who batted .270/.301/.338 and is an okay defender? Or a 26 year-old shortstop who hit .265/.321/.338 and plays superlative defense? Furthermore, the former is entering his walk year, whereas the younger is under contract for a reasonable $10.6 million per year over the next five years.

Um, I'll take the world-class defender who's half a decade younger. Apparently the Atlanta Braves would rather have the other guy.

In a bizarre trade that makes absolutely no sense to me, the rebuilding Atlanta Braves traded Andrelton Simmons to the Los Angeles Angels for Erick Aybar. In this swap of shortstops, the Angels are clearly getting the better one. They get an in-his-prime, two-time Gold Glove winner who'll be around for the rest of the decade. The Braves get a placeholder for a year and a pair of pitching prospects. The two starters are highly regarded, but when it comes to prospects--pitchers in particular--you just never know.

Especially wild ones like Sean Newcomb and Chris Ellis, who placed eighth and 47th last year in walk rate among the 578 pitchers who threw at least 100 innings (thanks to Jeff Sullivan at FanGraphs for the info). Obviously wildness can be tamed--see Sandy Koufax and Randy Johnson-- and the Braves are known for developing great pitchers, but there's a real chance neither of them ever pan out. They're risks.

In Simmons, they had a sure thing; an elite gloveman who wasn't a total liability with the bat, a guy who's been worth roughly 17 wins through his first 500 games. Since debuting in 2012, Simmons has been baseball's fifth-most valuable shortstop despite playing just 49 games in his abbreviated rookie season.

Number six, interestingly enough, is Aybar. But Aybar, as mentioned, is going to be 32 next year. His defense has slipped noticeably the last couple years, and he just posted his lowest OPS since 2010. He still has a little bit of speed, but not enough to compensate for his eroding skills at the plate and in the field. He'll be an average major league shortstop at best in 2016, with the very real possibility that he drops below replacement level.

That's not going to happen to Simmons for some time, simply because he's such an outstanding defender. He could be a black hole on offense and still save enough runs with his glove to be an everyday shortstop. He'd be much more valuable, of course, if he could combine last year's decent OBP (.321) with the 17 homers he hit in 2013, but there's nothing wrong with being a slicker-fielding Elvis Andrus type who doesn't run.

I'm just baffled as to why Atlanta would give up on Simmons so soon after locking him in to a team-friendly contract. He has not progressed with the stick as hoped, so maybe they feel his value will never be higher than it is right now, before his defense declines and drags down his worth. 2,000 plate appearances into his major league career, Simmons has failed to show he can be even an average major league hitter, so the Braves might be on to something there.

Still, quality shortstops don't just grow on trees, and it's hard to be much better than Simmons has over the past few years. That's why the Red Sox didn't move Xander Bogaerts when he was struggling last year; because young, controllable shortstops are worth their weight in gold. The Halos were wise to swap out Aybar for Simmons, especially with no viable replacement on the horizon. Rather than overpay to keep Aybar or go through a revolving door of shortstops a la Boston circa 2004-2013, they ensured stability at the position for the foreseeable future. (They also get a catching prospect to boot, though it doesn't look like he'll amount to much after posting a sub-.500 OPS last year).

I'm sure finances played a role in this exchange as well. Aybar's only under contract for one more year and will cost Atlanta a modest $6 million, as LA is picking up $2.5 million of the price tag to split the difference between his and Simmons' salaries. Simmons, on the other hand, is owed $53 million over the next five years. Maybe the Braves felt that was a contract they needed to get out from under, even though they had no problem ponying up $44 million for Nick Markakis last winter. In reality, though, Simmons is an absolute steal at that price. He only needs to be worth seven or eight wins over the next five years to earn his keep, which should be a breeze as long as he stays healthy (he was worth seven wins in 2013 alone).

As with all trades, we won't be able to judge this one for a while. The Angels addressed their short-term needs and got the best player in the deal (as of now), whereas the Braves saved some money and stocked their farm system. For now both teams are winners, though my gut's telling me history will favor Los Angeles on this one.