The St. Louis Cardinals are considering trading key players as part of their offseason rebuild after finishing with an 83-79 record and missing the playoffs for the second year in a row.

While Sonny Gray and Willson Contreras have expressed their desire to stay, Nolan Arenado and Ryan Helsley may be on the trading block. Helsley is expected to yield a strong return, potentially including top prospects like Baltimore Orioles' Coby Mayo.

Mayo had a successful minor league season but struggled in his brief MLB stint. If acquired, he could enhance the Cardinals' young roster.