What happened in 2016: Had an outstanding rookie campaign, good for a unanimous Rookie of the Year selection and third place in NL MVP voting.
Corey Seager made a strong first impression as a September call-up in 2015, batting .337/.425/.561/.986 in 113 plate appearances. That performance created unrealistic expectations for him, but he followed that up by somehow surpassing those expectations in his first full season in the majors.
The year started off relatively slowly for Seager, who posted a decent-but-not-amazing .707 OPS for the month of April. But things picked up for him in May, and even more so in June.