In 2013 and 2015, Chris Davis was the top slugger in baseball. He hit a combined 100 homers over those two seasons (53 in 2013 and 47 in 2015, leading MLB both times), was worth a combined 12.5 wins above replacement according to FanGraphs (fWAR).
Now, well, Davis is the worst regular in the majors. In 2017, he had a miserable slash line of .168/.243/.296, hit just 16 homers in 522 plate appearances, and was worth -3.1 fWAR (yes, that’s negative three wins). Unfortunately, the struggles have carried over to 2019 for Davis, and resulted in him setting an embarrassing record.