However, the latter will be returning to San Diego after leaving his first start with an elbow injury. The Marlins announced Monday that they traded Rea back to the Padres in exchange for pitcher Luis Castillo. Ken Rosenthal of Fox Sports first reported the deal.
At the time of the original deal, Rosenthal reported that pitcher Tayron Guerrero was traded to Miami along with Cashner and Rea. In return, San Diego received Jarred Cosart, Josh Naylor, Luis Castillo and pitcher Carter Capps.
Acquiring Cashner gives the Marlins starting rotation depth behind ace Jose Fernandez, which is desperately needed to make a deep playoff run. Jon Morosi of MLB Network reported that Miami made the original move for Cashner and Rea in part because Fernandez's innings are "likely to be restricted."
This season continues the downward spiral for the Padres, though at least they have now taken steps toward rebuilding for the future by trading James Shields and Drew Pomeranz before shipping Cashner to the Marlins.
Cashner was one of the "old" veterans in San Diego, playing with the franchise since being acquired in a deal with the Chicago Cubs in January 2012. He has dealt with injuries and inconsistency throughout his career.
This season has been problematic for Cashner, who owns a 4-7 record with a 4.54 ERA, 1.34 WHIP and 69 strikeouts in 85.1 innings.
He has shown signs of life recently, though, allowing one earned run in four of his past six starts.
Even so, there are glaring red flags that Cashner's new team has to consider. He's made more than 25 starts and reached the 175-inning plateau just twice in seven seasons.
Pitching primarily in Petco Park should have kept Cashner's ERA down, but after compiling a 2.87 ERA in 50 games between 2013 and 2014, it has jumped to well over 4.00 the past two years.
This is a classic buy-low trade for Miami that could look like a bargain at the end of this season. Cashner has his work cut out to reach his full potential, but the talent is there for him to be a good investment at a reduced cost.
He is set to hit free agency at the conclusion of the season, so this move looks to be a pure rental meant to push the Marlins over the top and into the playoffs for the first time since 2003, when they won the World Series.
While Cashner isn't having a great year by any means, Miami's starting rotation is likely its biggest weakness. Fernandez is unhittable at times, and Adam Conley has performed well behind him. But Tom Koehler has struggled, while Wei-Yin Chen is on the disabled list.
The Marlins desperately need an arm capable of eating innings and keeping them in games. Rea would have provided some insurance in that regard, and the Marlins will have to pivot before Monday's trade deadline to address Rea's absence.
However, if Cashner can stay healthy down the stretch and maintain his recent form, then he should at least give the team some solid outings at a reasonable price.
Stats via FanGraphs unless otherwise noted.