What the Astros Gave Up
Let’s start with Cosart, who was the apparent centerpiece of this deal at the time. He was a 38th-round draft pick by the Phillies in 2008 and came to Houston in the Hunter Pence trade in 2011. He burst onto the scene as a 23-year-old in 2013 by pitching to a 1.95 ERA in 10 starts, though his peripherals were not good. He walked more batters than he struck out, and FIP had him pegged at a much higher 4.35.
In 2014 prior to the trade, he was 9-7 with a 4.41 ERA in 20 starts for the Astros. After the trade, he went 4-4 with a 2.39 ERA in 10 starts for the fish. He made only 13 starts and one relief appearance in 2015, going 2-5 with a 4.52 ERA. He pitched to a 5.95 ERA in four starts in 2016 before being traded to the Padres in a seven-player deal. We’ll go into detail on that trade later, but for now let’s just say the Marlins didn’t make out all that well.
Cosart put up a 5.58 ERA in parts of two seasons with the Padres and hasn’t pitched in the majors since. He provided a total 1.8 WAR for the Marlins, mostly thanks to his strong 10-start run in 2014. This came after he’d put up 2.9 WAR in parts of two seasons in Houston.
Hernandez made his major league debut with the Astros in 2014, hitting .284/.348/.420 in 24 games. He hit only .175 in 18 games for the Marlins after the trade and was traded that offseason to the Dodgers in a deal that sent Dee Gordon to Miami. The Dodgers also got catcher Austin Barnes, reliever Chris Hatcher and starting pitcher Andrew Heaney, the latter of whom was immediately flipped to the Angels. The Marlins also got pitcher Dan Haren and infielder Miguel Rojas.
Hernandez quickly became a valuable utility player for the Dodgers, hitting .307 in 2015 and popping 21 homers in 2018. He’s played all the infield and outfield positions and has been worth 6.0 WAR for the Dodgers. In his brief stint with the Marlins, he was worth 0.2 WAR.
Wates was a former third-round draft pick who never reached the major leagues. He last played in the minors in 2015, so he ended up providing no value to the Marlins.