A couple years in the Oakland lineup pushed Marcus Semien to respectable power numbers with a middling batting average and double-digit stolen bases year after year. He popped 27 long balls in 2016, despite a .238 average. However, he only hit 25 home runs in the next two seasons, but then 2019 hit. And so did Semien. He played all 162 games, hit a career-best .285 and also posted career highs in home runs (33), runs scored (123), runs batted in (92), ISO (.237), on-base percentage (.369) and slugging percentage (.522), among others. So, after a year of career-bests, regression was likely. However, the extent of which it happened was surprising.

Across 53 games, he hit seven home runs, but his .152 ISO reverted back to his ways...