MLB Trades: Aroldis Chapman and 4 other trade deadline movers that aged like milk in the sun

4) The Marlins trade for David Robertson aging poorly

For the first time in a long time, the Miami Marlins were in position to go for it. They did so at the trade deadline, with their first big move being with their division rival. The Marlins gave up two promising prospects in exchange for David Robertson who at the time looked like the best relief pitcher on the market. Mets fans thought they could've gotten more, Marlins fans were excited. The tone has since flipped dramatically.

After blowing just three of his 17 save opportunities with the Mets, Robertson has blown three of his seven with the Marlins. He's taken four losses already with Miami in just 12 appearances while losing twice in 40 appearances with the Mets. Wins and losses as a pitching stat doesn't mean anything, but it's certainly saying something for a closer to have four losses in 12 appearances.

Robertson has gone from a 2.05 ERA with the Mets to a 7.50 ERA with Miami in his 12 innings of work. He's already been taken out of the closer's role, and appeared in the sixth inning his last time out.

Robertson isn't the only reason Miami has gone from a playoff spot to a team on the outside looking in, but he certainly hasn't done anything to make them better. The Marlins can still make the playoffs and the battle-tested Robertson can turn his season around a bit, but for now, this is a trade that's aging horribly for Kim Ng.