The struggling Marlins traded away two somewhat expensive players in Mat Latos and Michael Morse. In total, the Marlins will clear about $14 million in salary from their books. The Marlins look like they'll be on the hook for no part of either player's salary for the rest of this year and next year in Morse's case. The Marlins also gave up a draft pick, which is the fifth pick of the competitive balance round, but that pick might be a little better when/if free agents with qualifying offers sign contracts elsewhere.
In return, the Marlins get three pitching prospects from the Dodgers. This deal is large and complicated, involving the Braves and Dodgers, so it will be split up. I'll cover the deal from the Marlins' perspective, so I'll offer analysis on what they gave up, what they received, and their thought process. Read about the Dodgers' perspective here and the Braves' perspective here.
The Dodgers get a young (he is still only 27), good pitcher in Latos to fill out their rotation. After a poor start to the year, Latos is pitching very well. There is quite a clear trend in his monthly splits (wOBA allowed), arbitrary as they are:
Mar/Apr --> May --> June --> July
.387 --> .314 --> .298 --> .190
Latos has been truly excellent in July, giving up only two extra-base hits in the whole month (a double and a homer). His overall season line of 4.48 ERA / 3.34 FIP / 3.55 xFIP also reflects a little bad luck, as his left on base rate is well below average at 65.1 percent. However, his BABIP sits at .297, a normal value. There's actually something else going on regarding Latos' LOB rate.
Latos' wOBA allowed with nobody on base: .279.
Latos' wOBA allowed with men on base: .343
Latos' wOBA allowed with men in scoring position: .356
Latos is doing a poor job of maintaining his production when somebody gets on base. Early in his career (2009 and 2010) Latos had the same problem, but his overall career numbers don't suggest that this is a real thing. Latos' wOBA allowed in each situation above for his career is .285 / .297 / .289.
It's possible that this is just random variation. That's my guess. However, it's possible that it's a real thing. I wrote an article back in April comparing Latos' mechanics against Tim Lincecum's. Their body types and mechanics are almost on opposite extremes; Latos is big with slow mechanics not designed to generate velocity, while Lincecum's mechanics help him generate velocity from a slight frame. Again, I'm going with the random variation explanation, but it's possible that something in Latos' mechanics is preventing him from performing as well as he used to when he pitches from the stretch.
The other player, Michael Morse, somehow keeps finding a job in the league in which he is forced to play on the field. Morse had a great offensive season with San Francisco last year (a 133 wRC+), but his utter lack of defensive value held down his fWAR to only 0.9. The Marlins signed him to a two-year contract with the plan of hiding his defensive liability at first base. That worked to an extent; Morse was more-or-less acceptable at first with a DRS of -1, a UZR of -0.5, and nothing significant in his Inside Edge defensive numbers. The problem is with Morse's offense.
So far, Morse is sporting a .214/.277/.314 line for a 65 wRC+. He's missed time due to injury. While the contract wasn't for an amount of money that makes large-market teams squirm, the Marlins likely saw his contract as an albatross that had to be sent away.
Morse's poor offensive performance is not necessarily due to luck; his .297 BABIP is lower than his career .331 BABIP, but it's his batted ball distribution that is most to blame. After a fairly normal 45.2 percent ground ball rate last year, Morse's grounder rate has jumped to 57.1 percent this year. Morse is not the type of guy who should be legging out infield hits.
When Morse has elevated the ball, which has been rare, he's actually done a good amount of damage. Despite hardly ever pulling the ball on fly balls, he's still managed a .318 BA / 1.000 SLG on fly balls. His HR/FB is still a high 18.2 percent. He's still hitting the ball in the air pretty hard. It's the grounders that are killing his production. Not only is he hitting more of them, but he's producing only a .133 BA / .133 SLG on them, which is terrible. Due to poor walk and strikeout rates, Morse's production depends entirely on his ability to elevate the ball. He's just not doing that this year.
As for the return, the Marlins received Jeff Brigham, Victor Araujo, and Kevin Guzman. This is not a big return for the Marlins. In Kiley McDaniel's preseason Dodgers prospect writeup, he didn't even mention Araujo and Guzman. Brigham, a fourth round pick from 2014, was mentioned only near the end as somebody to keep an eye on. Brigham is currently in high A as a starter and struggling with control (11.3 percent walk rate). He's also 23. McDaniel said that Brigham's repertoire, a high-90s fastball with perhaps an average slider, is more suited for a relief role.
Araujo is a 25-year-old reliever in high A ball. Or is he 22? FanGraphs and Baseball America appear to have different birth dates. He has decent strikeout and walk rates, but he's running a 5.40 ERA / 4.10 FIP. A Baseball America article from 2014 noted that Araujo had a good slider but lacked a good fastball.
Kevin Guzman is a 20-year-old righty starter in A ball. His walk and strikeout rates are nothing special, but he is running a 3.90 ERA / 3.79 FIP due to an excellent home run rate. His ERA isn't bloated despite a high BABIP and low left-on-base rate.
None of the prospects the Marlins received was ranked highly within the Dodgers system, let alone overall. Again, this is because the Marlins were apparently more concerned with dumping salary than getting a good return. Guzman could pan out into something, but he's a long way away.
The thought is that the Marlins just wanted to get rid of each player's salary (Morse's more so since he had guaranteed money next year) in a losing season, and so they essentially "sold" their draft pick to accomplish that. Because the Marlins were apparently unwilling to keep any salary, they didn't get much in terms of prospect quality. The Braves and Dodgers entered the equation because they are willing to take on bad contracts at the moment to get something of value as well.
The interesting question is if the Marlins had other options. Clearly, they wanted to unload Morse, who is performing so poorly this season that I'm certain no one else wanted to take on his contract without receiving some good stuff. The Marlins, by deciding they had to unload his contract, pigeonholed themselves into seriously sweetening the deal. Enter the Dodgers, whose monetary concerns are like dandelions floating in the breeze, and the Braves, who are treating a rebuild like an NBA team (an interesting strategy). The Dodgers are willing to take on salary, but they also needed some help in the rotation (I guess. Do they really?). Mat Latos was available, and there was the framework of a deal.
Had the Marlins decided to trade Latos without trying to unload Morse, things could have been different.
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