Nolan Arenado missed the final week of the season as he recovered from a back injury. He was pretty much the best out of a bad situation for the Cardinals this year, but he still performed quite well.
However, he too found himself in a tough position when trade rumors began to circulate. Jorge Castillo of the Los Angeles Times reported that the Cardinals and Dodgers had discussed a trade for Arenado, and it took John Mozeliak several days to come out and finally say that the Cards weren't going to trade him.
Arenado also revealed that Mozeliak and the front office hadn't said anything to him about a potential trade.
It's also worth noting that the Cardinals were able to convince him not to opt out of his contract. However, they did not build a contending team around him, essentially breaking their promise to the star third baseman.